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/kernel.h>
  20 #include <linux/bio.h>
  21 #include <linux/buffer_head.h>
  22 #include <linux/file.h>
  23 #include <linux/fs.h>
  24 #include <linux/pagemap.h>
  25 #include <linux/highmem.h>
  26 #include <linux/time.h>
  27 #include <linux/init.h>
  28 #include <linux/string.h>
  29 #include <linux/smp_lock.h>
  30 #include <linux/backing-dev.h>
  31 #include <linux/mpage.h>
  32 #include <linux/swap.h>
  33 #include <linux/writeback.h>
  34 #include <linux/statfs.h>
  35 #include <linux/compat.h>
  36 #include <linux/bit_spinlock.h>
  37 #include <linux/version.h>
  38 #include <linux/xattr.h>
  39 #include <linux/posix_acl.h>
  40 #include "ctree.h"
  41 #include "disk-io.h"
  42 #include "transaction.h"
  43 #include "btrfs_inode.h"
  44 #include "ioctl.h"
  45 #include "print-tree.h"
  46 #include "volumes.h"
  47 #include "ordered-data.h"
  48
  49 struct btrfs_iget_args {
  50         u64 ino;
  51         struct btrfs_root *root;
  52 };
  53
  54 static struct inode_operations btrfs_dir_inode_operations;
  55 static struct inode_operations btrfs_symlink_inode_operations;
  56 static struct inode_operations btrfs_dir_ro_inode_operations;
  57 static struct inode_operations btrfs_special_inode_operations;
  58 static struct inode_operations btrfs_file_inode_operations;
  59 static struct address_space_operations btrfs_aops;
  60 static struct address_space_operations btrfs_symlink_aops;
  61 static struct file_operations btrfs_dir_file_operations;
  62 static struct extent_io_ops btrfs_extent_io_ops;
  63
  64 static struct kmem_cache *btrfs_inode_cachep;
  65 struct kmem_cache *btrfs_trans_handle_cachep;
  66 struct kmem_cache *btrfs_transaction_cachep;
  67 struct kmem_cache *btrfs_bit_radix_cachep;
  68 struct kmem_cache *btrfs_path_cachep;
  69
  70 #define S_SHIFT 12
  71 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
  72         [S_IFREG >> S_SHIFT]    = BTRFS_FT_REG_FILE,
  73         [S_IFDIR >> S_SHIFT]    = BTRFS_FT_DIR,
  74         [S_IFCHR >> S_SHIFT]    = BTRFS_FT_CHRDEV,
  75         [S_IFBLK >> S_SHIFT]    = BTRFS_FT_BLKDEV,
  76         [S_IFIFO >> S_SHIFT]    = BTRFS_FT_FIFO,
  77         [S_IFSOCK >> S_SHIFT]   = BTRFS_FT_SOCK,
  78         [S_IFLNK >> S_SHIFT]    = BTRFS_FT_SYMLINK,
  79 };
  80
  81 static void btrfs_truncate(struct inode *inode);
  82
  83 int btrfs_check_free_space(struct btrfs_root *root, u64 num_required,
  84                            int for_del)
  85 {
  86         u64 total;
  87         u64 used;
  88         u64 thresh;
  89         unsigned long flags;
  90         int ret = 0;
  91
  92         spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
  93         total = btrfs_super_total_bytes(&root->fs_info->super_copy);
  94         used = btrfs_super_bytes_used(&root->fs_info->super_copy);
  95         if (for_del)
  96                 thresh = total * 90;
  97         else
  98                 thresh = total * 85;
  99
 100         do_div(thresh, 100);
 101
 102         if (used + root->fs_info->delalloc_bytes + num_required > thresh)
 103                 ret = -ENOSPC;
 104         spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
 105         return ret;
 106 }
 107
 108 static int cow_file_range(struct inode *inode, u64 start, u64 end)
 109 {
 110         struct btrfs_root *root = BTRFS_I(inode)->root;
 111         struct btrfs_trans_handle *trans;
 112         u64 alloc_hint = 0;
 113         u64 num_bytes;
 114         u64 cur_alloc_size;
 115         u64 blocksize = root->sectorsize;
 116         u64 orig_num_bytes;
 117         struct btrfs_key ins;
 118         struct extent_map *em;
 119         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 120         int ret = 0;
 121
 122         trans = btrfs_join_transaction(root, 1);
 123         BUG_ON(!trans);
 124         btrfs_set_trans_block_group(trans, inode);
 125
 126         num_bytes = (end - start + blocksize) & ~(blocksize - 1);
 127         num_bytes = max(blocksize,  num_bytes);
 128         orig_num_bytes = num_bytes;
 129
 130         if (alloc_hint == EXTENT_MAP_INLINE)
 131                 goto out;
 132
 133         BUG_ON(num_bytes > btrfs_super_total_bytes(&root->fs_info->super_copy));
 134         mutex_lock(&BTRFS_I(inode)->extent_mutex);
 135         btrfs_drop_extent_cache(inode, start, start + num_bytes - 1);
 136         mutex_unlock(&BTRFS_I(inode)->extent_mutex);
 137
 138         while(num_bytes > 0) {
 139                 cur_alloc_size = min(num_bytes, root->fs_info->max_extent);
 140                 ret = btrfs_reserve_extent(trans, root, cur_alloc_size,
 141                                            root->sectorsize, 0, 0,
 142                                            (u64)-1, &ins, 1);
 143                 if (ret) {
 144                         WARN_ON(1);
 145                         goto out;
 146                 }
 147                 em = alloc_extent_map(GFP_NOFS);
 148                 em->start = start;
 149                 em->len = ins.offset;
 150                 em->block_start = ins.objectid;
 151                 em->bdev = root->fs_info->fs_devices->latest_bdev;
 152                 mutex_lock(&BTRFS_I(inode)->extent_mutex);
 153                 set_bit(EXTENT_FLAG_PINNED, &em->flags);
 154                 while(1) {
 155                         spin_lock(&em_tree->lock);
 156                         ret = add_extent_mapping(em_tree, em);
 157                         spin_unlock(&em_tree->lock);
 158                         if (ret != -EEXIST) {
 159                                 free_extent_map(em);
 160                                 break;
 161                         }
 162                         btrfs_drop_extent_cache(inode, start,
 163                                                 start + ins.offset - 1);
 164                 }
 165                 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
 166
 167                 cur_alloc_size = ins.offset;
 168                 ret = btrfs_add_ordered_extent(inode, start, ins.objectid,
 169                                                ins.offset);
 170                 BUG_ON(ret);
 171                 if (num_bytes < cur_alloc_size) {
 172                         printk("num_bytes %Lu cur_alloc %Lu\n", num_bytes,
 173                                cur_alloc_size);
 174                         break;
 175                 }
 176                 num_bytes -= cur_alloc_size;
 177                 alloc_hint = ins.objectid + ins.offset;
 178                 start += cur_alloc_size;
 179         }
 180 out:
 181         btrfs_end_transaction(trans, root);
 182         return ret;
 183 }
 184
 185 static int run_delalloc_nocow(struct inode *inode, u64 start, u64 end)
 186 {
 187         u64 extent_start;
 188         u64 extent_end;
 189         u64 bytenr;
 190         u64 cow_end;
 191         u64 loops = 0;
 192         u64 total_fs_bytes;
 193         struct btrfs_root *root = BTRFS_I(inode)->root;
 194         struct btrfs_block_group_cache *block_group;
 195         struct extent_buffer *leaf;
 196         int found_type;
 197         struct btrfs_path *path;
 198         struct btrfs_file_extent_item *item;
 199         int ret;
 200         int err;
 201         struct btrfs_key found_key;
 202
 203         total_fs_bytes = btrfs_super_total_bytes(&root->fs_info->super_copy);
 204         path = btrfs_alloc_path();
 205         BUG_ON(!path);
 206 again:
 207         ret = btrfs_lookup_file_extent(NULL, root, path,
 208                                        inode->i_ino, start, 0);
 209         if (ret < 0) {
 210                 btrfs_free_path(path);
 211                 return ret;
 212         }
 213
 214         cow_end = end;
 215         if (ret != 0) {
 216                 if (path->slots[0] == 0)
 217                         goto not_found;
 218                 path->slots[0]--;
 219         }
 220
 221         leaf = path->nodes[0];
 222         item = btrfs_item_ptr(leaf, path->slots[0],
 223                               struct btrfs_file_extent_item);
 224
 225         /* are we inside the extent that was found? */
 226         btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 227         found_type = btrfs_key_type(&found_key);
 228         if (found_key.objectid != inode->i_ino ||
 229             found_type != BTRFS_EXTENT_DATA_KEY)
 230                 goto not_found;
 231
 232         found_type = btrfs_file_extent_type(leaf, item);
 233         extent_start = found_key.offset;
 234         if (found_type == BTRFS_FILE_EXTENT_REG) {
 235                 u64 extent_num_bytes;
 236
 237                 extent_num_bytes = btrfs_file_extent_num_bytes(leaf, item);
 238                 extent_end = extent_start + extent_num_bytes;
 239                 err = 0;
 240
 241                 if (loops && start != extent_start)
 242                         goto not_found;
 243
 244                 if (start < extent_start || start >= extent_end)
 245                         goto not_found;
 246
 247                 cow_end = min(end, extent_end - 1);
 248                 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
 249                 if (bytenr == 0)
 250                         goto not_found;
 251
 252                 if (btrfs_cross_ref_exists(root, &found_key, bytenr))
 253                         goto not_found;
 254                 /*
 255                  * we may be called by the resizer, make sure we're inside
 256                  * the limits of the FS
 257                  */
 258                 block_group = btrfs_lookup_block_group(root->fs_info,
 259                                                        bytenr);
 260                 if (!block_group || block_group->ro)
 261                         goto not_found;
 262
 263                 start = extent_end;
 264         } else {
 265                 goto not_found;
 266         }
 267 loop:
 268         if (start > end) {
 269                 btrfs_free_path(path);
 270                 return 0;
 271         }
 272         btrfs_release_path(root, path);
 273         loops++;
 274         goto again;
 275
 276 not_found:
 277         btrfs_release_path(root, path);
 278         cow_file_range(inode, start, end);
 279         start = end + 1;
 280         goto loop;
 281 }
 282
 283 static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
 284 {
 285         struct btrfs_root *root = BTRFS_I(inode)->root;
 286         int ret;
 287
 288         if (btrfs_test_opt(root, NODATACOW) ||
 289             btrfs_test_flag(inode, NODATACOW))
 290                 ret = run_delalloc_nocow(inode, start, end);
 291         else
 292                 ret = cow_file_range(inode, start, end);
 293
 294         return ret;
 295 }
 296
 297 int btrfs_set_bit_hook(struct inode *inode, u64 start, u64 end,
 298                        unsigned long old, unsigned long bits)
 299 {
 300         unsigned long flags;
 301         if (!(old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
 302                 struct btrfs_root *root = BTRFS_I(inode)->root;
 303                 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
 304                 BTRFS_I(inode)->delalloc_bytes += end - start + 1;
 305                 root->fs_info->delalloc_bytes += end - start + 1;
 306                 if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
 307                         list_add_tail(&BTRFS_I(inode)->delalloc_inodes,
 308                                       &root->fs_info->delalloc_inodes);
 309                 }
 310                 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
 311         }
 312         return 0;
 313 }
 314
 315 int btrfs_clear_bit_hook(struct inode *inode, u64 start, u64 end,
 316                          unsigned long old, unsigned long bits)
 317 {
 318         if ((old & EXTENT_DELALLOC) && (bits & EXTENT_DELALLOC)) {
 319                 struct btrfs_root *root = BTRFS_I(inode)->root;
 320                 unsigned long flags;
 321
 322                 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
 323                 if (end - start + 1 > root->fs_info->delalloc_bytes) {
 324                         printk("warning: delalloc account %Lu %Lu\n",
 325                                end - start + 1, root->fs_info->delalloc_bytes);
 326                         root->fs_info->delalloc_bytes = 0;
 327                         BTRFS_I(inode)->delalloc_bytes = 0;
 328                 } else {
 329                         root->fs_info->delalloc_bytes -= end - start + 1;
 330                         BTRFS_I(inode)->delalloc_bytes -= end - start + 1;
 331                 }
 332                 if (BTRFS_I(inode)->delalloc_bytes == 0 &&
 333                     !list_empty(&BTRFS_I(inode)->delalloc_inodes)) {
 334                         list_del_init(&BTRFS_I(inode)->delalloc_inodes);
 335                 }
 336                 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
 337         }
 338         return 0;
 339 }
 340
 341 int btrfs_merge_bio_hook(struct page *page, unsigned long offset,
 342                          size_t size, struct bio *bio)
 343 {
 344         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 345         struct btrfs_mapping_tree *map_tree;
 346         u64 logical = bio->bi_sector << 9;
 347         u64 length = 0;
 348         u64 map_length;
 349         int ret;
 350
 351         length = bio->bi_size;
 352         map_tree = &root->fs_info->mapping_tree;
 353         map_length = length;
 354         ret = btrfs_map_block(map_tree, READ, logical,
 355                               &map_length, NULL, 0);
 356
 357         if (map_length < length + size) {
 358                 return 1;
 359         }
 360         return 0;
 361 }
 362
 363 int __btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 364                           int mirror_num)
 365 {
 366         struct btrfs_root *root = BTRFS_I(inode)->root;
 367         int ret = 0;
 368
 369         ret = btrfs_csum_one_bio(root, inode, bio);
 370         BUG_ON(ret);
 371
 372         return btrfs_map_bio(root, rw, bio, mirror_num, 1);
 373 }
 374
 375 int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
 376                           int mirror_num)
 377 {
 378         struct btrfs_root *root = BTRFS_I(inode)->root;
 379         int ret = 0;
 380
 381         ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0);
 382         BUG_ON(ret);
 383
 384         if (!(rw & (1 << BIO_RW))) {
 385                 goto mapit;
 386         }
 387
 388         return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info,
 389                                    inode, rw, bio, mirror_num,
 390                                    __btrfs_submit_bio_hook);
 391 mapit:
 392         return btrfs_map_bio(root, rw, bio, mirror_num, 0);
 393 }
 394
 395 static noinline int add_pending_csums(struct btrfs_trans_handle *trans,
 396                              struct inode *inode, u64 file_offset,
 397                              struct list_head *list)
 398 {
 399         struct list_head *cur;
 400         struct btrfs_ordered_sum *sum;
 401
 402         btrfs_set_trans_block_group(trans, inode);
 403         list_for_each(cur, list) {
 404                 sum = list_entry(cur, struct btrfs_ordered_sum, list);
 405                 mutex_lock(&BTRFS_I(inode)->csum_mutex);
 406                 btrfs_csum_file_blocks(trans, BTRFS_I(inode)->root,
 407                                        inode, sum);
 408                 mutex_unlock(&BTRFS_I(inode)->csum_mutex);
 409         }
 410         return 0;
 411 }
 412
 413 int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end)
 414 {
 415         return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end,
 416                                    GFP_NOFS);
 417 }
 418
 419 struct btrfs_writepage_fixup {
 420         struct page *page;
 421         struct btrfs_work work;
 422 };
 423
 424 /* see btrfs_writepage_start_hook for details on why this is required */
 425 void btrfs_writepage_fixup_worker(struct btrfs_work *work)
 426 {
 427         struct btrfs_writepage_fixup *fixup;
 428         struct btrfs_ordered_extent *ordered;
 429         struct page *page;
 430         struct inode *inode;
 431         u64 page_start;
 432         u64 page_end;
 433
 434         fixup = container_of(work, struct btrfs_writepage_fixup, work);
 435         page = fixup->page;
 436 again:
 437         lock_page(page);
 438         if (!page->mapping || !PageDirty(page) || !PageChecked(page)) {
 439                 ClearPageChecked(page);
 440                 goto out_page;
 441         }
 442
 443         inode = page->mapping->host;
 444         page_start = page_offset(page);
 445         page_end = page_offset(page) + PAGE_CACHE_SIZE - 1;
 446
 447         lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
 448
 449         /* already ordered? We're done */
 450         if (test_range_bit(&BTRFS_I(inode)->io_tree, page_start, page_end,
 451                              EXTENT_ORDERED, 0)) {
 452                 goto out;
 453         }
 454
 455         ordered = btrfs_lookup_ordered_extent(inode, page_start);
 456         if (ordered) {
 457                 unlock_extent(&BTRFS_I(inode)->io_tree, page_start,
 458                               page_end, GFP_NOFS);
 459                 unlock_page(page);
 460                 btrfs_start_ordered_extent(inode, ordered, 1);
 461                 goto again;
 462         }
 463
 464         btrfs_set_extent_delalloc(inode, page_start, page_end);
 465         ClearPageChecked(page);
 466 out:
 467         unlock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end, GFP_NOFS);
 468 out_page:
 469         unlock_page(page);
 470         page_cache_release(page);
 471 }
 472
 473 /*
 474  * There are a few paths in the higher layers of the kernel that directly
 475  * set the page dirty bit without asking the filesystem if it is a
 476  * good idea.  This causes problems because we want to make sure COW
 477  * properly happens and the data=ordered rules are followed.
 478  *
 479  * In our case any range that doesn't have the EXTENT_ORDERED bit set
 480  * hasn't been properly setup for IO.  We kick off an async process
 481  * to fix it up.  The async helper will wait for ordered extents, set
 482  * the delalloc bit and make it safe to write the page.
 483  */
 484 int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
 485 {
 486         struct inode *inode = page->mapping->host;
 487         struct btrfs_writepage_fixup *fixup;
 488         struct btrfs_root *root = BTRFS_I(inode)->root;
 489         int ret;
 490
 491         ret = test_range_bit(&BTRFS_I(inode)->io_tree, start, end,
 492                              EXTENT_ORDERED, 0);
 493         if (ret)
 494                 return 0;
 495
 496         if (PageChecked(page))
 497                 return -EAGAIN;
 498
 499         fixup = kzalloc(sizeof(*fixup), GFP_NOFS);
 500         if (!fixup)
 501                 return -EAGAIN;
 502
 503         SetPageChecked(page);
 504         page_cache_get(page);
 505         fixup->work.func = btrfs_writepage_fixup_worker;
 506         fixup->page = page;
 507         btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work);
 508         return -EAGAIN;
 509 }
 510
 511 static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
 512 {
 513         struct btrfs_root *root = BTRFS_I(inode)->root;
 514         struct btrfs_trans_handle *trans;
 515         struct btrfs_ordered_extent *ordered_extent;
 516         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 517         u64 alloc_hint = 0;
 518         struct list_head list;
 519         struct btrfs_key ins;
 520         int ret;
 521
 522         ret = btrfs_dec_test_ordered_pending(inode, start, end - start + 1);
 523         if (!ret)
 524                 return 0;
 525
 526         trans = btrfs_join_transaction(root, 1);
 527
 528         ordered_extent = btrfs_lookup_ordered_extent(inode, start);
 529         BUG_ON(!ordered_extent);
 530
 531         lock_extent(io_tree, ordered_extent->file_offset,
 532                     ordered_extent->file_offset + ordered_extent->len - 1,
 533                     GFP_NOFS);
 534
 535         INIT_LIST_HEAD(&list);
 536
 537         ins.objectid = ordered_extent->start;
 538         ins.offset = ordered_extent->len;
 539         ins.type = BTRFS_EXTENT_ITEM_KEY;
 540
 541         ret = btrfs_alloc_reserved_extent(trans, root, root->root_key.objectid,
 542                                           trans->transid, inode->i_ino,
 543                                           ordered_extent->file_offset, &ins);
 544         BUG_ON(ret);
 545
 546         mutex_lock(&BTRFS_I(inode)->extent_mutex);
 547
 548         ret = btrfs_drop_extents(trans, root, inode,
 549                                  ordered_extent->file_offset,
 550                                  ordered_extent->file_offset +
 551                                  ordered_extent->len,
 552                                  ordered_extent->file_offset, &alloc_hint);
 553         BUG_ON(ret);
 554         ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
 555                                        ordered_extent->file_offset,
 556                                        ordered_extent->start,
 557                                        ordered_extent->len,
 558                                        ordered_extent->len, 0);
 559         BUG_ON(ret);
 560
 561         btrfs_drop_extent_cache(inode, ordered_extent->file_offset,
 562                                 ordered_extent->file_offset +
 563                                 ordered_extent->len - 1);
 564         mutex_unlock(&BTRFS_I(inode)->extent_mutex);
 565
 566         inode->i_blocks += ordered_extent->len >> 9;
 567         unlock_extent(io_tree, ordered_extent->file_offset,
 568                     ordered_extent->file_offset + ordered_extent->len - 1,
 569                     GFP_NOFS);
 570         add_pending_csums(trans, inode, ordered_extent->file_offset,
 571                           &ordered_extent->list);
 572
 573         btrfs_ordered_update_i_size(inode, ordered_extent);
 574         btrfs_remove_ordered_extent(inode, ordered_extent);
 575
 576         /* once for us */
 577         btrfs_put_ordered_extent(ordered_extent);
 578         /* once for the tree */
 579         btrfs_put_ordered_extent(ordered_extent);
 580
 581         btrfs_update_inode(trans, root, inode);
 582         btrfs_end_transaction(trans, root);
 583         return 0;
 584 }
 585
 586 int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
 587                                 struct extent_state *state, int uptodate)
 588 {
 589         return btrfs_finish_ordered_io(page->mapping->host, start, end);
 590 }
 591
 592 int btrfs_readpage_io_hook(struct page *page, u64 start, u64 end)
 593 {
 594         int ret = 0;
 595         struct inode *inode = page->mapping->host;
 596         struct btrfs_root *root = BTRFS_I(inode)->root;
 597         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 598         struct btrfs_csum_item *item;
 599         struct btrfs_path *path = NULL;
 600         u32 csum;
 601
 602         if (btrfs_test_opt(root, NODATASUM) ||
 603             btrfs_test_flag(inode, NODATASUM))
 604                 return 0;
 605
 606         /*
 607          * It is possible there is an ordered extent that has
 608          * not yet finished for this range in the file.  If so,
 609          * that extent will have a csum cached, and it will insert
 610          * the sum after all the blocks in the extent are fully
 611          * on disk.  So, look for an ordered extent and use the
 612          * sum if found.  We have to do this before looking in the
 613          * btree because csum items are pre-inserted based on
 614          * the file size.  btrfs_lookup_csum might find an item
 615          * that still hasn't been fully filled.
 616          */
 617         ret = btrfs_find_ordered_sum(inode, start, &csum);
 618         if (ret == 0)
 619                 goto found;
 620
 621         ret = 0;
 622         path = btrfs_alloc_path();
 623         item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, start, 0);
 624         if (IS_ERR(item)) {
 625                 ret = PTR_ERR(item);
 626                 /* a csum that isn't present is a preallocated region. */
 627                 if (ret == -ENOENT || ret == -EFBIG)
 628                         ret = 0;
 629                 csum = 0;
 630                 printk("no csum found for inode %lu start %Lu\n", inode->i_ino,
 631                        start);
 632                 goto out;
 633         }
 634         read_extent_buffer(path->nodes[0], &csum, (unsigned long)item,
 635                            BTRFS_CRC32_SIZE);
 636 found:
 637         set_state_private(io_tree, start, csum);
 638 out:
 639         if (path)
 640                 btrfs_free_path(path);
 641         return ret;
 642 }
 643
 644 struct io_failure_record {
 645         struct page *page;
 646         u64 start;
 647         u64 len;
 648         u64 logical;
 649         int last_mirror;
 650 };
 651
 652 int btrfs_io_failed_hook(struct bio *failed_bio,
 653                          struct page *page, u64 start, u64 end,
 654                          struct extent_state *state)
 655 {
 656         struct io_failure_record *failrec = NULL;
 657         u64 private;
 658         struct extent_map *em;
 659         struct inode *inode = page->mapping->host;
 660         struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
 661         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 662         struct bio *bio;
 663         int num_copies;
 664         int ret;
 665         int rw;
 666         u64 logical;
 667
 668         ret = get_state_private(failure_tree, start, &private);
 669         if (ret) {
 670                 failrec = kmalloc(sizeof(*failrec), GFP_NOFS);
 671                 if (!failrec)
 672                         return -ENOMEM;
 673                 failrec->start = start;
 674                 failrec->len = end - start + 1;
 675                 failrec->last_mirror = 0;
 676
 677                 spin_lock(&em_tree->lock);
 678                 em = lookup_extent_mapping(em_tree, start, failrec->len);
 679                 if (em->start > start || em->start + em->len < start) {
 680                         free_extent_map(em);
 681                         em = NULL;
 682                 }
 683                 spin_unlock(&em_tree->lock);
 684
 685                 if (!em || IS_ERR(em)) {
 686                         kfree(failrec);
 687                         return -EIO;
 688                 }
 689                 logical = start - em->start;
 690                 logical = em->block_start + logical;
 691                 failrec->logical = logical;
 692                 free_extent_map(em);
 693                 set_extent_bits(failure_tree, start, end, EXTENT_LOCKED |
 694                                 EXTENT_DIRTY, GFP_NOFS);
 695                 set_state_private(failure_tree, start,
 696                                  (u64)(unsigned long)failrec);
 697         } else {
 698                 failrec = (struct io_failure_record *)(unsigned long)private;
 699         }
 700         num_copies = btrfs_num_copies(
 701                               &BTRFS_I(inode)->root->fs_info->mapping_tree,
 702                               failrec->logical, failrec->len);
 703         failrec->last_mirror++;
 704         if (!state) {
 705                 spin_lock_irq(&BTRFS_I(inode)->io_tree.lock);
 706                 state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
 707                                                     failrec->start,
 708                                                     EXTENT_LOCKED);
 709                 if (state && state->start != failrec->start)
 710                         state = NULL;
 711                 spin_unlock_irq(&BTRFS_I(inode)->io_tree.lock);
 712         }
 713         if (!state || failrec->last_mirror > num_copies) {
 714                 set_state_private(failure_tree, failrec->start, 0);
 715                 clear_extent_bits(failure_tree, failrec->start,
 716                                   failrec->start + failrec->len - 1,
 717                                   EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
 718                 kfree(failrec);
 719                 return -EIO;
 720         }
 721         bio = bio_alloc(GFP_NOFS, 1);
 722         bio->bi_private = state;
 723         bio->bi_end_io = failed_bio->bi_end_io;
 724         bio->bi_sector = failrec->logical >> 9;
 725         bio->bi_bdev = failed_bio->bi_bdev;
 726         bio->bi_size = 0;
 727         bio_add_page(bio, page, failrec->len, start - page_offset(page));
 728         if (failed_bio->bi_rw & (1 << BIO_RW))
 729                 rw = WRITE;
 730         else
 731                 rw = READ;
 732
 733         BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
 734                                                       failrec->last_mirror);
 735         return 0;
 736 }
 737
 738 int btrfs_clean_io_failures(struct inode *inode, u64 start)
 739 {
 740         u64 private;
 741         u64 private_failure;
 742         struct io_failure_record *failure;
 743         int ret;
 744
 745         private = 0;
 746         if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
 747                              (u64)-1, 1, EXTENT_DIRTY)) {
 748                 ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
 749                                         start, &private_failure);
 750                 if (ret == 0) {
 751                         failure = (struct io_failure_record *)(unsigned long)
 752                                    private_failure;
 753                         set_state_private(&BTRFS_I(inode)->io_failure_tree,
 754                                           failure->start, 0);
 755                         clear_extent_bits(&BTRFS_I(inode)->io_failure_tree,
 756                                           failure->start,
 757                                           failure->start + failure->len - 1,
 758                                           EXTENT_DIRTY | EXTENT_LOCKED,
 759                                           GFP_NOFS);
 760                         kfree(failure);
 761                 }
 762         }
 763         return 0;
 764 }
 765
 766 int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end,
 767                                struct extent_state *state)
 768 {
 769         size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT);
 770         struct inode *inode = page->mapping->host;
 771         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 772         char *kaddr;
 773         u64 private = ~(u32)0;
 774         int ret;
 775         struct btrfs_root *root = BTRFS_I(inode)->root;
 776         u32 csum = ~(u32)0;
 777         unsigned long flags;
 778
 779         if (btrfs_test_opt(root, NODATASUM) ||
 780             btrfs_test_flag(inode, NODATASUM))
 781                 return 0;
 782         if (state && state->start == start) {
 783                 private = state->private;
 784                 ret = 0;
 785         } else {
 786                 ret = get_state_private(io_tree, start, &private);
 787         }
 788         local_irq_save(flags);
 789         kaddr = kmap_atomic(page, KM_IRQ0);
 790         if (ret) {
 791                 goto zeroit;
 792         }
 793         csum = btrfs_csum_data(root, kaddr + offset, csum,  end - start + 1);
 794         btrfs_csum_final(csum, (char *)&csum);
 795         if (csum != private) {
 796                 goto zeroit;
 797         }
 798         kunmap_atomic(kaddr, KM_IRQ0);
 799         local_irq_restore(flags);
 800
 801         /* if the io failure tree for this inode is non-empty,
 802          * check to see if we've recovered from a failed IO
 803          */
 804         btrfs_clean_io_failures(inode, start);
 805         return 0;
 806
 807 zeroit:
 808         printk("btrfs csum failed ino %lu off %llu csum %u private %Lu\n",
 809                page->mapping->host->i_ino, (unsigned long long)start, csum,
 810                private);
 811         memset(kaddr + offset, 1, end - start + 1);
 812         flush_dcache_page(page);
 813         kunmap_atomic(kaddr, KM_IRQ0);
 814         local_irq_restore(flags);
 815         if (private == 0)
 816                 return 0;
 817         return -EIO;
 818 }
 819
 820 /*
 821  * This creates an orphan entry for the given inode in case something goes
 822  * wrong in the middle of an unlink/truncate.
 823  */
 824 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
 825 {
 826         struct btrfs_root *root = BTRFS_I(inode)->root;
 827         int ret = 0;
 828
 829         spin_lock(&root->list_lock);
 830
 831         /* already on the orphan list, we're good */
 832         if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
 833                 spin_unlock(&root->list_lock);
 834                 return 0;
 835         }
 836
 837         list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
 838
 839         spin_unlock(&root->list_lock);
 840
 841         /*
 842          * insert an orphan item to track this unlinked/truncated file
 843          */
 844         ret = btrfs_insert_orphan_item(trans, root, inode->i_ino);
 845
 846         return ret;
 847 }
 848
 849 /*
 850  * We have done the truncate/delete so we can go ahead and remove the orphan
 851  * item for this particular inode.
 852  */
 853 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
 854 {
 855         struct btrfs_root *root = BTRFS_I(inode)->root;
 856         int ret = 0;
 857
 858         spin_lock(&root->list_lock);
 859
 860         if (list_empty(&BTRFS_I(inode)->i_orphan)) {
 861                 spin_unlock(&root->list_lock);
 862                 return 0;
 863         }
 864
 865         list_del_init(&BTRFS_I(inode)->i_orphan);
 866         if (!trans) {
 867                 spin_unlock(&root->list_lock);
 868                 return 0;
 869         }
 870
 871         spin_unlock(&root->list_lock);
 872
 873         ret = btrfs_del_orphan_item(trans, root, inode->i_ino);
 874
 875         return ret;
 876 }
 877
 878 /*
 879  * this cleans up any orphans that may be left on the list from the last use
 880  * of this root.
 881  */
 882 void btrfs_orphan_cleanup(struct btrfs_root *root)
 883 {
 884         struct btrfs_path *path;
 885         struct extent_buffer *leaf;
 886         struct btrfs_item *item;
 887         struct btrfs_key key, found_key;
 888         struct btrfs_trans_handle *trans;
 889         struct inode *inode;
 890         int ret = 0, nr_unlink = 0, nr_truncate = 0;
 891
 892         /* don't do orphan cleanup if the fs is readonly. */
 893         if (root->inode->i_sb->s_flags & MS_RDONLY)
 894                 return;
 895
 896         path = btrfs_alloc_path();
 897         if (!path)
 898                 return;
 899         path->reada = -1;
 900
 901         key.objectid = BTRFS_ORPHAN_OBJECTID;
 902         btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY);
 903         key.offset = (u64)-1;
 904
 905         trans = btrfs_start_transaction(root, 1);
 906         btrfs_set_trans_block_group(trans, root->inode);
 907
 908         while (1) {
 909                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
 910                 if (ret < 0) {
 911                         printk(KERN_ERR "Error searching slot for orphan: %d"
 912                                "\n", ret);
 913                         break;
 914                 }
 915
 916                 /*
 917                  * if ret == 0 means we found what we were searching for, which
 918                  * is weird, but possible, so only screw with path if we didnt
 919                  * find the key and see if we have stuff that matches
 920                  */
 921                 if (ret > 0) {
 922                         if (path->slots[0] == 0)
 923                                 break;
 924                         path->slots[0]--;
 925                 }
 926
 927                 /* pull out the item */
 928                 leaf = path->nodes[0];
 929                 item = btrfs_item_nr(leaf, path->slots[0]);
 930                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 931
 932                 /* make sure the item matches what we want */
 933                 if (found_key.objectid != BTRFS_ORPHAN_OBJECTID)
 934                         break;
 935                 if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY)
 936                         break;
 937
 938                 /* release the path since we're done with it */
 939                 btrfs_release_path(root, path);
 940
 941                 /*
 942                  * this is where we are basically btrfs_lookup, without the
 943                  * crossing root thing.  we store the inode number in the
 944                  * offset of the orphan item.
 945                  */
 946                 inode = btrfs_iget_locked(root->inode->i_sb,
 947                                           found_key.offset, root);
 948                 if (!inode)
 949                         break;
 950
 951                 if (inode->i_state & I_NEW) {
 952                         BTRFS_I(inode)->root = root;
 953
 954                         /* have to set the location manually */
 955                         BTRFS_I(inode)->location.objectid = inode->i_ino;
 956                         BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
 957                         BTRFS_I(inode)->location.offset = 0;
 958
 959                         btrfs_read_locked_inode(inode);
 960                         unlock_new_inode(inode);
 961                 }
 962
 963                 /*
 964                  * add this inode to the orphan list so btrfs_orphan_del does
 965                  * the proper thing when we hit it
 966                  */
 967                 spin_lock(&root->list_lock);
 968                 list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
 969                 spin_unlock(&root->list_lock);
 970
 971                 /*
 972                  * if this is a bad inode, means we actually succeeded in
 973                  * removing the inode, but not the orphan record, which means
 974                  * we need to manually delete the orphan since iput will just
 975                  * do a destroy_inode
 976                  */
 977                 if (is_bad_inode(inode)) {
 978                         btrfs_orphan_del(trans, inode);
 979                         iput(inode);
 980                         continue;
 981                 }
 982
 983                 /* if we have links, this was a truncate, lets do that */
 984                 if (inode->i_nlink) {
 985                         nr_truncate++;
 986                         btrfs_truncate(inode);
 987                 } else {
 988                         nr_unlink++;
 989                 }
 990
 991                 /* this will do delete_inode and everything for us */
 992                 iput(inode);
 993         }
 994
 995         if (nr_unlink)
 996                 printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
 997         if (nr_truncate)
 998                 printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
 999
1000         btrfs_free_path(path);
1001         btrfs_end_transaction(trans, root);
1002 }
1003
1004 void btrfs_read_locked_inode(struct inode *inode)
1005 {
1006         struct btrfs_path *path;
1007         struct extent_buffer *leaf;
1008         struct btrfs_inode_item *inode_item;
1009         struct btrfs_timespec *tspec;
1010         struct btrfs_root *root = BTRFS_I(inode)->root;
1011         struct btrfs_key location;
1012         u64 alloc_group_block;
1013         u32 rdev;
1014         int ret;
1015
1016         path = btrfs_alloc_path();
1017         BUG_ON(!path);
1018         memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
1019
1020         ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
1021         if (ret)
1022                 goto make_bad;
1023
1024         leaf = path->nodes[0];
1025         inode_item = btrfs_item_ptr(leaf, path->slots[0],
1026                                     struct btrfs_inode_item);
1027
1028         inode->i_mode = btrfs_inode_mode(leaf, inode_item);
1029         inode->i_nlink = btrfs_inode_nlink(leaf, inode_item);
1030         inode->i_uid = btrfs_inode_uid(leaf, inode_item);
1031         inode->i_gid = btrfs_inode_gid(leaf, inode_item);
1032         btrfs_i_size_write(inode, btrfs_inode_size(leaf, inode_item));
1033
1034         tspec = btrfs_inode_atime(inode_item);
1035         inode->i_atime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1036         inode->i_atime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1037
1038         tspec = btrfs_inode_mtime(inode_item);
1039         inode->i_mtime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1040         inode->i_mtime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1041
1042         tspec = btrfs_inode_ctime(inode_item);
1043         inode->i_ctime.tv_sec = btrfs_timespec_sec(leaf, tspec);
1044         inode->i_ctime.tv_nsec = btrfs_timespec_nsec(leaf, tspec);
1045
1046         inode->i_blocks = btrfs_inode_nblocks(leaf, inode_item);
1047         inode->i_generation = btrfs_inode_generation(leaf, inode_item);
1048         inode->i_rdev = 0;
1049         rdev = btrfs_inode_rdev(leaf, inode_item);
1050
1051         BTRFS_I(inode)->index_cnt = (u64)-1;
1052
1053         alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
1054         BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
1055                                                        alloc_group_block);
1056         BTRFS_I(inode)->flags = btrfs_inode_flags(leaf, inode_item);
1057         if (!BTRFS_I(inode)->block_group) {
1058                 BTRFS_I(inode)->block_group = btrfs_find_block_group(root,
1059                                                  NULL, 0,
1060                                                  BTRFS_BLOCK_GROUP_METADATA, 0);
1061         }
1062         btrfs_free_path(path);
1063         inode_item = NULL;
1064
1065         switch (inode->i_mode & S_IFMT) {
1066         case S_IFREG:
1067                 inode->i_mapping->a_ops = &btrfs_aops;
1068                 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
1069                 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
1070                 inode->i_fop = &btrfs_file_operations;
1071                 inode->i_op = &btrfs_file_inode_operations;
1072                 break;
1073         case S_IFDIR:
1074                 inode->i_fop = &btrfs_dir_file_operations;
1075                 if (root == root->fs_info->tree_root)
1076                         inode->i_op = &btrfs_dir_ro_inode_operations;
1077                 else
1078                         inode->i_op = &btrfs_dir_inode_operations;
1079                 break;
1080         case S_IFLNK:
1081                 inode->i_op = &btrfs_symlink_inode_operations;
1082                 inode->i_mapping->a_ops = &btrfs_symlink_aops;
1083                 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
1084                 break;
1085         default:
1086                 init_special_inode(inode, inode->i_mode, rdev);
1087                 break;
1088         }
1089         return;
1090
1091 make_bad:
1092         btrfs_free_path(path);
1093         make_bad_inode(inode);
1094 }
1095
1096 static void fill_inode_item(struct extent_buffer *leaf,
1097                             struct btrfs_inode_item *item,
1098                             struct inode *inode)
1099 {
1100         btrfs_set_inode_uid(leaf, item, inode->i_uid);
1101         btrfs_set_inode_gid(leaf, item, inode->i_gid);
1102         btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size);
1103         btrfs_set_inode_mode(leaf, item, inode->i_mode);
1104         btrfs_set_inode_nlink(leaf, item, inode->i_nlink);
1105
1106         btrfs_set_timespec_sec(leaf, btrfs_inode_atime(item),
1107                                inode->i_atime.tv_sec);
1108         btrfs_set_timespec_nsec(leaf, btrfs_inode_atime(item),
1109                                 inode->i_atime.tv_nsec);
1110
1111         btrfs_set_timespec_sec(leaf, btrfs_inode_mtime(item),
1112                                inode->i_mtime.tv_sec);
1113         btrfs_set_timespec_nsec(leaf, btrfs_inode_mtime(item),
1114                                 inode->i_mtime.tv_nsec);
1115
1116         btrfs_set_timespec_sec(leaf, btrfs_inode_ctime(item),
1117                                inode->i_ctime.tv_sec);
1118         btrfs_set_timespec_nsec(leaf, btrfs_inode_ctime(item),
1119                                 inode->i_ctime.tv_nsec);
1120
1121         btrfs_set_inode_nblocks(leaf, item, inode->i_blocks);
1122         btrfs_set_inode_generation(leaf, item, inode->i_generation);
1123         btrfs_set_inode_rdev(leaf, item, inode->i_rdev);
1124         btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags);
1125         btrfs_set_inode_block_group(leaf, item,
1126                                     BTRFS_I(inode)->block_group->key.objectid);
1127 }
1128
1129 int noinline btrfs_update_inode(struct btrfs_trans_handle *trans,
1130                               struct btrfs_root *root,
1131                               struct inode *inode)
1132 {
1133         struct btrfs_inode_item *inode_item;
1134         struct btrfs_path *path;
1135         struct extent_buffer *leaf;
1136         int ret;
1137
1138         path = btrfs_alloc_path();
1139         BUG_ON(!path);
1140         ret = btrfs_lookup_inode(trans, root, path,
1141                                  &BTRFS_I(inode)->location, 1);
1142         if (ret) {
1143                 if (ret > 0)
1144                         ret = -ENOENT;
1145                 goto failed;
1146         }
1147
1148         leaf = path->nodes[0];
1149         inode_item = btrfs_item_ptr(leaf, path->slots[0],
1150                                   struct btrfs_inode_item);
1151
1152         fill_inode_item(leaf, inode_item, inode);
1153         btrfs_mark_buffer_dirty(leaf);
1154         btrfs_set_inode_last_trans(trans, inode);
1155         ret = 0;
1156 failed:
1157         btrfs_free_path(path);
1158         return ret;
1159 }
1160
1161
1162 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
1163                               struct btrfs_root *root,
1164                               struct inode *dir,
1165                               struct dentry *dentry)
1166 {
1167         struct btrfs_path *path;
1168         const char *name = dentry->d_name.name;
1169         int name_len = dentry->d_name.len;
1170         int ret = 0;
1171         struct extent_buffer *leaf;
1172         struct btrfs_dir_item *di;
1173         struct btrfs_key key;
1174         u64 index;
1175
1176         path = btrfs_alloc_path();
1177         if (!path) {
1178                 ret = -ENOMEM;
1179                 goto err;
1180         }
1181
1182         di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
1183                                     name, name_len, -1);
1184         if (IS_ERR(di)) {
1185                 ret = PTR_ERR(di);
1186                 goto err;
1187         }
1188         if (!di) {
1189                 ret = -ENOENT;
1190                 goto err;
1191         }
1192         leaf = path->nodes[0];
1193         btrfs_dir_item_key_to_cpu(leaf, di, &key);
1194         ret = btrfs_delete_one_dir_name(trans, root, path, di);
1195         if (ret)
1196                 goto err;
1197         btrfs_release_path(root, path);
1198
1199         ret = btrfs_del_inode_ref(trans, root, name, name_len,
1200                                   dentry->d_inode->i_ino,
1201                                   dentry->d_parent->d_inode->i_ino, &index);
1202         if (ret) {
1203                 printk("failed to delete reference to %.*s, "
1204                        "inode %lu parent %lu\n", name_len, name,
1205                        dentry->d_inode->i_ino,
1206                        dentry->d_parent->d_inode->i_ino);
1207                 goto err;
1208         }
1209
1210         di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
1211                                          index, name, name_len, -1);
1212         if (IS_ERR(di)) {
1213                 ret = PTR_ERR(di);
1214                 goto err;
1215         }
1216         if (!di) {
1217                 ret = -ENOENT;
1218                 goto err;
1219         }
1220         ret = btrfs_delete_one_dir_name(trans, root, path, di);
1221         btrfs_release_path(root, path);
1222
1223         dentry->d_inode->i_ctime = dir->i_ctime;
1224 err:
1225         btrfs_free_path(path);
1226         if (!ret) {
1227                 btrfs_i_size_write(dir, dir->i_size - name_len * 2);
1228                 dir->i_mtime = dir->i_ctime = CURRENT_TIME;
1229                 btrfs_update_inode(trans, root, dir);
1230 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
1231                 dentry->d_inode->i_nlink--;
1232 #else
1233                 drop_nlink(dentry->d_inode);
1234 #endif
1235                 ret = btrfs_update_inode(trans, root, dentry->d_inode);
1236                 dir->i_sb->s_dirt = 1;
1237         }
1238         return ret;
1239 }
1240
1241 static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
1242 {
1243         struct btrfs_root *root;
1244         struct btrfs_trans_handle *trans;
1245         struct inode *inode = dentry->d_inode;
1246         int ret;
1247         unsigned long nr = 0;
1248
1249         root = BTRFS_I(dir)->root;
1250
1251         ret = btrfs_check_free_space(root, 1, 1);
1252         if (ret)
1253                 goto fail;
1254
1255         trans = btrfs_start_transaction(root, 1);
1256
1257         btrfs_set_trans_block_group(trans, dir);
1258         ret = btrfs_unlink_trans(trans, root, dir, dentry);
1259
1260         if (inode->i_nlink == 0)
1261                 ret = btrfs_orphan_add(trans, inode);
1262
1263         nr = trans->blocks_used;
1264
1265         btrfs_end_transaction_throttle(trans, root);
1266 fail:
1267         btrfs_btree_balance_dirty(root, nr);
1268         return ret;
1269 }
1270
1271 static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
1272 {
1273         struct inode *inode = dentry->d_inode;
1274         int err = 0;
1275         int ret;
1276         struct btrfs_root *root = BTRFS_I(dir)->root;
1277         struct btrfs_trans_handle *trans;
1278         unsigned long nr = 0;
1279
1280         if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
1281                 return -ENOTEMPTY;
1282         }
1283
1284         ret = btrfs_check_free_space(root, 1, 1);
1285         if (ret)
1286                 goto fail;
1287
1288         trans = btrfs_start_transaction(root, 1);
1289         btrfs_set_trans_block_group(trans, dir);
1290
1291         err = btrfs_orphan_add(trans, inode);
1292         if (err)
1293                 goto fail_trans;
1294
1295         /* now the directory is empty */
1296         err = btrfs_unlink_trans(trans, root, dir, dentry);
1297         if (!err) {
1298                 btrfs_i_size_write(inode, 0);
1299         }
1300
1301 fail_trans:
1302         nr = trans->blocks_used;
1303         ret = btrfs_end_transaction_throttle(trans, root);
1304 fail:
1305         btrfs_btree_balance_dirty(root, nr);
1306
1307         if (ret && !err)
1308                 err = ret;
1309         return err;
1310 }
1311
1312 /*
1313  * this can truncate away extent items, csum items and directory items.
1314  * It starts at a high offset and removes keys until it can't find
1315  * any higher than i_size.
1316  *
1317  * csum items that cross the new i_size are truncated to the new size
1318  * as well.
1319  *
1320  * min_type is the minimum key type to truncate down to.  If set to 0, this
1321  * will kill all the items on this inode, including the INODE_ITEM_KEY.
1322  */
1323 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
1324                                    struct btrfs_root *root,
1325                                    struct inode *inode,
1326                                    u32 min_type)
1327 {
1328         int ret;
1329         struct btrfs_path *path;
1330         struct btrfs_key key;
1331         struct btrfs_key found_key;
1332         u32 found_type;
1333         struct extent_buffer *leaf;
1334         struct btrfs_file_extent_item *fi;
1335         u64 extent_start = 0;
1336         u64 extent_num_bytes = 0;
1337         u64 item_end = 0;
1338         u64 root_gen = 0;
1339         u64 root_owner = 0;
1340         int found_extent;
1341         int del_item;
1342         int pending_del_nr = 0;
1343         int pending_del_slot = 0;
1344         int extent_type = -1;
1345         u64 mask = root->sectorsize - 1;
1346
1347         btrfs_drop_extent_cache(inode, inode->i_size & (~mask), (u64)-1);
1348         path = btrfs_alloc_path();
1349         path->reada = -1;
1350         BUG_ON(!path);
1351
1352         /* FIXME, add redo link to tree so we don't leak on crash */
1353         key.objectid = inode->i_ino;
1354         key.offset = (u64)-1;
1355         key.type = (u8)-1;
1356
1357         btrfs_init_path(path);
1358 search_again:
1359         ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
1360         if (ret < 0) {
1361                 goto error;
1362         }
1363         if (ret > 0) {
1364                 BUG_ON(path->slots[0] == 0);
1365                 path->slots[0]--;
1366         }
1367
1368         while(1) {
1369                 fi = NULL;
1370                 leaf = path->nodes[0];
1371                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1372                 found_type = btrfs_key_type(&found_key);
1373
1374                 if (found_key.objectid != inode->i_ino)
1375                         break;
1376
1377                 if (found_type < min_type)
1378                         break;
1379
1380                 item_end = found_key.offset;
1381                 if (found_type == BTRFS_EXTENT_DATA_KEY) {
1382                         fi = btrfs_item_ptr(leaf, path->slots[0],
1383                                             struct btrfs_file_extent_item);
1384                         extent_type = btrfs_file_extent_type(leaf, fi);
1385                         if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
1386                                 item_end +=
1387                                     btrfs_file_extent_num_bytes(leaf, fi);
1388                         } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1389                                 struct btrfs_item *item = btrfs_item_nr(leaf,
1390                                                                 path->slots[0]);
1391                                 item_end += btrfs_file_extent_inline_len(leaf,
1392                                                                          item);
1393                         }
1394                         item_end--;
1395                 }
1396                 if (found_type == BTRFS_CSUM_ITEM_KEY) {
1397                         ret = btrfs_csum_truncate(trans, root, path,
1398                                                   inode->i_size);
1399                         BUG_ON(ret);
1400                 }
1401                 if (item_end < inode->i_size) {
1402                         if (found_type == BTRFS_DIR_ITEM_KEY) {
1403                                 found_type = BTRFS_INODE_ITEM_KEY;
1404                         } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
1405                                 found_type = BTRFS_CSUM_ITEM_KEY;
1406                         } else if (found_type == BTRFS_EXTENT_DATA_KEY) {
1407                                 found_type = BTRFS_XATTR_ITEM_KEY;
1408                         } else if (found_type == BTRFS_XATTR_ITEM_KEY) {
1409                                 found_type = BTRFS_INODE_REF_KEY;
1410                         } else if (found_type) {
1411                                 found_type--;
1412                         } else {
1413                                 break;
1414                         }
1415                         btrfs_set_key_type(&key, found_type);
1416                         goto next;
1417                 }
1418                 if (found_key.offset >= inode->i_size)
1419                         del_item = 1;
1420                 else
1421                         del_item = 0;
1422                 found_extent = 0;
1423
1424                 /* FIXME, shrink the extent if the ref count is only 1 */
1425                 if (found_type != BTRFS_EXTENT_DATA_KEY)
1426                         goto delete;
1427
1428                 if (extent_type != BTRFS_FILE_EXTENT_INLINE) {
1429                         u64 num_dec;
1430                         extent_start = btrfs_file_extent_disk_bytenr(leaf, fi);
1431                         if (!del_item) {
1432                                 u64 orig_num_bytes =
1433                                         btrfs_file_extent_num_bytes(leaf, fi);
1434                                 extent_num_bytes = inode->i_size -
1435                                         found_key.offset + root->sectorsize - 1;
1436                                 extent_num_bytes = extent_num_bytes &
1437                                         ~((u64)root->sectorsize - 1);
1438                                 btrfs_set_file_extent_num_bytes(leaf, fi,
1439                                                          extent_num_bytes);
1440                                 num_dec = (orig_num_bytes -
1441                                            extent_num_bytes);
1442                                 if (extent_start != 0)
1443                                         dec_i_blocks(inode, num_dec);
1444                                 btrfs_mark_buffer_dirty(leaf);
1445                         } else {
1446                                 extent_num_bytes =
1447                                         btrfs_file_extent_disk_num_bytes(leaf,
1448                                                                          fi);
1449                                 /* FIXME blocksize != 4096 */
1450                                 num_dec = btrfs_file_extent_num_bytes(leaf, fi);
1451                                 if (extent_start != 0) {
1452                                         found_extent = 1;
1453                                         dec_i_blocks(inode, num_dec);
1454                                 }
1455                                 root_gen = btrfs_header_generation(leaf);
1456                                 root_owner = btrfs_header_owner(leaf);
1457                         }
1458                 } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
1459                         if (!del_item) {
1460                                 u32 newsize = inode->i_size - found_key.offset;
1461                                 dec_i_blocks(inode, item_end + 1 -
1462                                             found_key.offset - newsize);
1463                                 newsize =
1464                                     btrfs_file_extent_calc_inline_size(newsize);
1465                                 ret = btrfs_truncate_item(trans, root, path,
1466                                                           newsize, 1);
1467                                 BUG_ON(ret);
1468                         } else {
1469                                 dec_i_blocks(inode, item_end + 1 -
1470                                              found_key.offset);
1471                         }
1472                 }
1473 delete:
1474                 if (del_item) {
1475                         if (!pending_del_nr) {
1476                                 /* no pending yet, add ourselves */
1477                                 pending_del_slot = path->slots[0];
1478                                 pending_del_nr = 1;
1479                         } else if (pending_del_nr &&
1480                                    path->slots[0] + 1 == pending_del_slot) {
1481                                 /* hop on the pending chunk */
1482                                 pending_del_nr++;
1483                                 pending_del_slot = path->slots[0];
1484                         } else {
1485                                 printk("bad pending slot %d pending_del_nr %d pending_del_slot %d\n", path->slots[0], pending_del_nr, pending_del_slot);
1486                         }
1487                 } else {
1488                         break;
1489                 }
1490                 if (found_extent) {
1491                         ret = btrfs_free_extent(trans, root, extent_start,
1492                                                 extent_num_bytes,
1493                                                 root_owner,
1494                                                 root_gen, inode->i_ino,
1495                                                 found_key.offset, 0);
1496                         BUG_ON(ret);
1497                 }
1498 next:
1499                 if (path->slots[0] == 0) {
1500                         if (pending_del_nr)
1501                                 goto del_pending;
1502                         btrfs_release_path(root, path);
1503                         goto search_again;
1504                 }
1505
1506                 path->slots[0]--;
1507                 if (pending_del_nr &&
1508                     path->slots[0] + 1 != pending_del_slot) {
1509                         struct btrfs_key debug;
1510 del_pending:
1511                         btrfs_item_key_to_cpu(path->nodes[0], &debug,
1512                                               pending_del_slot);
1513                         ret = btrfs_del_items(trans, root, path,
1514                                               pending_del_slot,
1515                                               pending_del_nr);
1516                         BUG_ON(ret);
1517                         pending_del_nr = 0;
1518                         btrfs_release_path(root, path);
1519                         goto search_again;
1520                 }
1521         }
1522         ret = 0;
1523 error:
1524         if (pending_del_nr) {
1525                 ret = btrfs_del_items(trans, root, path, pending_del_slot,
1526                                       pending_del_nr);
1527         }
1528         btrfs_free_path(path);
1529         inode->i_sb->s_dirt = 1;
1530         return ret;
1531 }
1532
1533 /*
1534  * taken from block_truncate_page, but does cow as it zeros out
1535  * any bytes left in the last page in the file.
1536  */
1537 static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
1538 {
1539         struct inode *inode = mapping->host;
1540         struct btrfs_root *root = BTRFS_I(inode)->root;
1541         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1542         struct btrfs_ordered_extent *ordered;
1543         char *kaddr;
1544         u32 blocksize = root->sectorsize;
1545         pgoff_t index = from >> PAGE_CACHE_SHIFT;
1546         unsigned offset = from & (PAGE_CACHE_SIZE-1);
1547         struct page *page;
1548         int ret = 0;
1549         u64 page_start;
1550         u64 page_end;
1551
1552         if ((offset & (blocksize - 1)) == 0)
1553                 goto out;
1554
1555         ret = -ENOMEM;
1556 again:
1557         page = grab_cache_page(mapping, index);
1558         if (!page)
1559                 goto out;
1560
1561         page_start = page_offset(page);
1562         page_end = page_start + PAGE_CACHE_SIZE - 1;
1563
1564         if (!PageUptodate(page)) {
1565                 ret = btrfs_readpage(NULL, page);
1566                 lock_page(page);
1567                 if (page->mapping != mapping) {
1568                         unlock_page(page);
1569                         page_cache_release(page);
1570                         goto again;
1571                 }
1572                 if (!PageUptodate(page)) {
1573                         ret = -EIO;
1574                         goto out_unlock;
1575                 }
1576         }
1577         wait_on_page_writeback(page);
1578
1579         lock_extent(io_tree, page_start, page_end, GFP_NOFS);
1580         set_page_extent_mapped(page);
1581
1582         ordered = btrfs_lookup_ordered_extent(inode, page_start);
1583         if (ordered) {
1584                 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
1585                 unlock_page(page);
1586                 page_cache_release(page);
1587                 btrfs_start_ordered_extent(inode, ordered, 1);
1588                 btrfs_put_ordered_extent(ordered);
1589                 goto again;
1590         }
1591
1592         btrfs_set_extent_delalloc(inode, page_start, page_end);
1593         ret = 0;
1594         if (offset != PAGE_CACHE_SIZE) {
1595                 kaddr = kmap(page);
1596                 memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
1597                 flush_dcache_page(page);
1598                 kunmap(page);
1599         }
1600         ClearPageChecked(page);
1601         set_page_dirty(page);
1602         unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
1603
1604 out_unlock:
1605         unlock_page(page);
1606         page_cache_release(page);
1607 out:
1608         return ret;
1609 }
1610
1611 static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
1612 {
1613         struct inode *inode = dentry->d_inode;
1614         int err;
1615
1616         err = inode_change_ok(inode, attr);
1617         if (err)
1618                 return err;
1619
1620         if (S_ISREG(inode->i_mode) &&
1621             attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
1622                 struct btrfs_trans_handle *trans;
1623                 struct btrfs_root *root = BTRFS_I(inode)->root;
1624                 struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1625
1626                 u64 mask = root->sectorsize - 1;
1627                 u64 hole_start = (inode->i_size + mask) & ~mask;
1628                 u64 block_end = (attr->ia_size + mask) & ~mask;
1629                 u64 hole_size;
1630                 u64 alloc_hint = 0;
1631
1632                 if (attr->ia_size <= hole_start)
1633                         goto out;
1634
1635                 err = btrfs_check_free_space(root, 1, 0);
1636                 if (err)
1637                         goto fail;
1638
1639                 btrfs_truncate_page(inode->i_mapping, inode->i_size);
1640
1641                 hole_size = block_end - hole_start;
1642                 btrfs_wait_ordered_range(inode, hole_start, hole_size);
1643                 lock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
1644
1645                 trans = btrfs_start_transaction(root, 1);
1646                 btrfs_set_trans_block_group(trans, inode);
1647                 mutex_lock(&BTRFS_I(inode)->extent_mutex);
1648                 err = btrfs_drop_extents(trans, root, inode,
1649                                          hole_start, block_end, hole_start,
1650                                          &alloc_hint);
1651
1652                 if (alloc_hint != EXTENT_MAP_INLINE) {
1653                         err = btrfs_insert_file_extent(trans, root,
1654                                                        inode->i_ino,
1655                                                        hole_start, 0, 0,
1656                                                        hole_size, 0);
1657                         btrfs_drop_extent_cache(inode, hole_start,
1658                                                 (u64)-1);
1659                         btrfs_check_file(root, inode);
1660                 }
1661                 mutex_unlock(&BTRFS_I(inode)->extent_mutex);
1662                 btrfs_end_transaction(trans, root);
1663                 unlock_extent(io_tree, hole_start, block_end - 1, GFP_NOFS);
1664                 if (err)
1665                         return err;
1666         }
1667 out:
1668         err = inode_setattr(inode, attr);
1669
1670         if (!err && ((attr->ia_valid & ATTR_MODE)))
1671                 err = btrfs_acl_chmod(inode);
1672 fail:
1673         return err;
1674 }
1675
1676 void btrfs_delete_inode(struct inode *inode)
1677 {
1678         struct btrfs_trans_handle *trans;
1679         struct btrfs_root *root = BTRFS_I(inode)->root;
1680         unsigned long nr;
1681         int ret;
1682
1683         truncate_inode_pages(&inode->i_data, 0);
1684         if (is_bad_inode(inode)) {
1685                 btrfs_orphan_del(NULL, inode);
1686                 goto no_delete;
1687         }
1688         btrfs_wait_ordered_range(inode, 0, (u64)-1);
1689
1690         btrfs_i_size_write(inode, 0);
1691         trans = btrfs_start_transaction(root, 1);
1692
1693         btrfs_set_trans_block_group(trans, inode);
1694         ret = btrfs_truncate_in_trans(trans, root, inode, 0);
1695         if (ret) {
1696                 btrfs_orphan_del(NULL, inode);
1697                 goto no_delete_lock;
1698         }
1699
1700         btrfs_orphan_del(trans, inode);
1701
1702         nr = trans->blocks_used;
1703         clear_inode(inode);
1704
1705         btrfs_end_transaction(trans, root);
1706         btrfs_btree_balance_dirty(root, nr);
1707         return;
1708
1709 no_delete_lock:
1710         nr = trans->blocks_used;
1711         btrfs_end_transaction(trans, root);
1712         btrfs_btree_balance_dirty(root, nr);
1713 no_delete:
1714         clear_inode(inode);
1715 }
1716
1717 /*
1718  * this returns the key found in the dir entry in the location pointer.
1719  * If no dir entries were found, location->objectid is 0.
1720  */
1721 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
1722                                struct btrfs_key *location)
1723 {
1724         const char *name = dentry->d_name.name;
1725         int namelen = dentry->d_name.len;
1726         struct btrfs_dir_item *di;
1727         struct btrfs_path *path;
1728         struct btrfs_root *root = BTRFS_I(dir)->root;
1729         int ret = 0;
1730
1731         if (namelen == 1 && strcmp(name, ".") == 0) {
1732                 location->objectid = dir->i_ino;
1733                 location->type = BTRFS_INODE_ITEM_KEY;
1734                 location->offset = 0;
1735                 return 0;
1736         }
1737         path = btrfs_alloc_path();
1738         BUG_ON(!path);
1739
1740         if (namelen == 2 && strcmp(name, "..") == 0) {
1741                 struct btrfs_key key;
1742                 struct extent_buffer *leaf;
1743                 int slot;
1744
1745                 key.objectid = dir->i_ino;
1746                 key.offset = (u64)-1;
1747                 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1748                 if (ret < 0 || path->slots[0] == 0)
1749                         goto out_err;
1750                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1751                 BUG_ON(ret == 0);
1752                 ret = 0;
1753                 leaf = path->nodes[0];
1754                 slot = path->slots[0] - 1;
1755
1756                 btrfs_item_key_to_cpu(leaf, &key, slot);
1757                 if (key.objectid != dir->i_ino ||
1758                     key.type != BTRFS_INODE_REF_KEY) {
1759                         goto out_err;
1760                 }
1761                 location->objectid = key.offset;
1762                 location->type = BTRFS_INODE_ITEM_KEY;
1763                 location->offset = 0;
1764                 goto out;
1765         }
1766
1767         di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
1768                                     namelen, 0);
1769         if (IS_ERR(di))
1770                 ret = PTR_ERR(di);
1771         if (!di || IS_ERR(di)) {
1772                 goto out_err;
1773         }
1774         btrfs_dir_item_key_to_cpu(path->nodes[0], di, location);
1775 out:
1776         btrfs_free_path(path);
1777         return ret;
1778 out_err:
1779         location->objectid = 0;
1780         goto out;
1781 }
1782
1783 /*
1784  * when we hit a tree root in a directory, the btrfs part of the inode
1785  * needs to be changed to reflect the root directory of the tree root.  This
1786  * is kind of like crossing a mount point.
1787  */
1788 static int fixup_tree_root_location(struct btrfs_root *root,
1789                              struct btrfs_key *location,
1790                              struct btrfs_root **sub_root,
1791                              struct dentry *dentry)
1792 {
1793         struct btrfs_root_item *ri;
1794
1795         if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
1796                 return 0;
1797         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
1798                 return 0;
1799
1800         *sub_root = btrfs_read_fs_root(root->fs_info, location,
1801                                         dentry->d_name.name,
1802                                         dentry->d_name.len);
1803         if (IS_ERR(*sub_root))
1804                 return PTR_ERR(*sub_root);
1805
1806         ri = &(*sub_root)->root_item;
1807         location->objectid = btrfs_root_dirid(ri);
1808         btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
1809         location->offset = 0;
1810
1811         return 0;
1812 }
1813
1814 static int btrfs_init_locked_inode(struct inode *inode, void *p)
1815 {
1816         struct btrfs_iget_args *args = p;
1817         inode->i_ino = args->ino;
1818         BTRFS_I(inode)->root = args->root;
1819         BTRFS_I(inode)->delalloc_bytes = 0;
1820         BTRFS_I(inode)->disk_i_size = 0;
1821         BTRFS_I(inode)->index_cnt = (u64)-1;
1822         extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
1823         extent_io_tree_init(&BTRFS_I(inode)->io_tree,
1824                              inode->i_mapping, GFP_NOFS);
1825         extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
1826                              inode->i_mapping, GFP_NOFS);
1827         INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
1828         btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
1829         mutex_init(&BTRFS_I(inode)->csum_mutex);
1830         mutex_init(&BTRFS_I(inode)->extent_mutex);
1831         return 0;
1832 }
1833
1834 static int btrfs_find_actor(struct inode *inode, void *opaque)
1835 {
1836         struct btrfs_iget_args *args = opaque;
1837         return (args->ino == inode->i_ino &&
1838                 args->root == BTRFS_I(inode)->root);
1839 }
1840
1841 struct inode *btrfs_ilookup(struct super_block *s, u64 objectid,
1842                             u64 root_objectid)
1843 {
1844         struct btrfs_iget_args args;
1845         args.ino = objectid;
1846         args.root = btrfs_lookup_fs_root(btrfs_sb(s)->fs_info, root_objectid);
1847
1848         if (!args.root)
1849                 return NULL;
1850
1851         return ilookup5(s, objectid, btrfs_find_actor, (void *)&args);
1852 }
1853
1854 struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
1855                                 struct btrfs_root *root)
1856 {
1857         struct inode *inode;
1858         struct btrfs_iget_args args;
1859         args.ino = objectid;
1860         args.root = root;
1861
1862         inode = iget5_locked(s, objectid, btrfs_find_actor,
1863                              btrfs_init_locked_inode,
1864                              (void *)&args);
1865         return inode;
1866 }
1867
1868 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
1869                                    struct nameidata *nd)
1870 {
1871         struct inode * inode;
1872         struct btrfs_inode *bi = BTRFS_I(dir);
1873         struct btrfs_root *root = bi->root;
1874         struct btrfs_root *sub_root = root;
1875         struct btrfs_key location;
1876         int ret, do_orphan = 0;
1877
1878         if (dentry->d_name.len > BTRFS_NAME_LEN)
1879                 return ERR_PTR(-ENAMETOOLONG);
1880
1881         ret = btrfs_inode_by_name(dir, dentry, &location);
1882
1883         if (ret < 0)
1884                 return ERR_PTR(ret);
1885
1886         inode = NULL;
1887         if (location.objectid) {
1888                 ret = fixup_tree_root_location(root, &location, &sub_root,
1889                                                 dentry);
1890                 if (ret < 0)
1891                         return ERR_PTR(ret);
1892                 if (ret > 0)
1893                         return ERR_PTR(-ENOENT);
1894
1895                 inode = btrfs_iget_locked(dir->i_sb, location.objectid,
1896                                           sub_root);
1897                 if (!inode)
1898                         return ERR_PTR(-EACCES);
1899                 if (inode->i_state & I_NEW) {
1900                         /* the inode and parent dir are two different roots */
1901                         if (sub_root != root) {
1902                                 igrab(inode);
1903                                 sub_root->inode = inode;
1904                                 do_orphan = 1;
1905                         }
1906                         BTRFS_I(inode)->root = sub_root;
1907                         memcpy(&BTRFS_I(inode)->location, &location,
1908                                sizeof(location));
1909                         btrfs_read_locked_inode(inode);
1910                         unlock_new_inode(inode);
1911                 }
1912         }
1913
1914         if (unlikely(do_orphan))
1915                 btrfs_orphan_cleanup(sub_root);
1916
1917         return d_splice_alias(inode, dentry);
1918 }
1919
1920 static unsigned char btrfs_filetype_table[] = {
1921         DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
1922 };
1923
1924 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
1925 {
1926         struct inode *inode = filp->f_dentry->d_inode;
1927         struct btrfs_root *root = BTRFS_I(inode)->root;
1928         struct btrfs_item *item;
1929         struct btrfs_dir_item *di;
1930         struct btrfs_key key;
1931         struct btrfs_key found_key;
1932         struct btrfs_path *path;
1933         int ret;
1934         u32 nritems;
1935         struct extent_buffer *leaf;
1936         int slot;
1937         int advance;
1938         unsigned char d_type;
1939         int over = 0;
1940         u32 di_cur;
1941         u32 di_total;
1942         u32 di_len;
1943         int key_type = BTRFS_DIR_INDEX_KEY;
1944         char tmp_name[32];
1945         char *name_ptr;
1946         int name_len;
1947
1948         /* FIXME, use a real flag for deciding about the key type */
1949         if (root->fs_info->tree_root == root)
1950                 key_type = BTRFS_DIR_ITEM_KEY;
1951
1952         /* special case for "." */
1953         if (filp->f_pos == 0) {
1954                 over = filldir(dirent, ".", 1,
1955                                1, inode->i_ino,
1956                                DT_DIR);
1957                 if (over)
1958                         return 0;
1959                 filp->f_pos = 1;
1960         }
1961
1962         key.objectid = inode->i_ino;
1963         path = btrfs_alloc_path();
1964         path->reada = 2;
1965
1966         /* special case for .., just use the back ref */
1967         if (filp->f_pos == 1) {
1968                 btrfs_set_key_type(&key, BTRFS_INODE_REF_KEY);
1969                 key.offset = (u64)-1;
1970                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1971                 if (ret < 0 || path->slots[0] == 0) {
1972                         btrfs_release_path(root, path);
1973                         goto read_dir_items;
1974                 }
1975                 BUG_ON(ret == 0);
1976                 leaf = path->nodes[0];
1977                 slot = path->slots[0] - 1;
1978                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
1979                 btrfs_release_path(root, path);
1980                 if (found_key.objectid != key.objectid ||
1981                     found_key.type != BTRFS_INODE_REF_KEY)
1982                         goto read_dir_items;
1983                 over = filldir(dirent, "..", 2,
1984                                2, found_key.offset, DT_DIR);
1985                 if (over)
1986                         goto nopos;
1987                 filp->f_pos = 2;
1988         }
1989
1990 read_dir_items:
1991         btrfs_set_key_type(&key, key_type);
1992         key.offset = filp->f_pos;
1993
1994         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1995         if (ret < 0)
1996                 goto err;
1997         advance = 0;
1998         while(1) {
1999                 leaf = path->nodes[0];
2000                 nritems = btrfs_header_nritems(leaf);
2001                 slot = path->slots[0];
2002                 if (advance || slot >= nritems) {
2003                         if (slot >= nritems -1) {
2004                                 ret = btrfs_next_leaf(root, path);
2005                                 if (ret)
2006                                         break;
2007                                 leaf = path->nodes[0];
2008                                 nritems = btrfs_header_nritems(leaf);
2009                                 slot = path->slots[0];
2010                         } else {
2011                                 slot++;
2012                                 path->slots[0]++;
2013                         }
2014                 }
2015                 advance = 1;
2016                 item = btrfs_item_nr(leaf, slot);
2017                 btrfs_item_key_to_cpu(leaf, &found_key, slot);
2018
2019                 if (found_key.objectid != key.objectid)
2020                         break;
2021                 if (btrfs_key_type(&found_key) != key_type)
2022                         break;
2023                 if (found_key.offset < filp->f_pos)
2024                         continue;
2025
2026                 filp->f_pos = found_key.offset;
2027                 advance = 1;
2028                 di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
2029                 di_cur = 0;
2030                 di_total = btrfs_item_size(leaf, item);
2031                 while(di_cur < di_total) {
2032                         struct btrfs_key location;
2033
2034                         name_len = btrfs_dir_name_len(leaf, di);
2035                         if (name_len < 32) {
2036                                 name_ptr = tmp_name;
2037                         } else {
2038                                 name_ptr = kmalloc(name_len, GFP_NOFS);
2039                                 BUG_ON(!name_ptr);
2040                         }
2041                         read_extent_buffer(leaf, name_ptr,
2042                                            (unsigned long)(di + 1), name_len);
2043
2044                         d_type = btrfs_filetype_table[btrfs_dir_type(leaf, di)];
2045                         btrfs_dir_item_key_to_cpu(leaf, di, &location);
2046                         over = filldir(dirent, name_ptr, name_len,
2047                                        found_key.offset,
2048                                        location.objectid,
2049                                        d_type);
2050
2051                         if (name_ptr != tmp_name)
2052                                 kfree(name_ptr);
2053
2054                         if (over)
2055                                 goto nopos;
2056                         di_len = btrfs_dir_name_len(leaf, di) +
2057                                 btrfs_dir_data_len(leaf, di) +sizeof(*di);
2058                         di_cur += di_len;
2059                         di = (struct btrfs_dir_item *)((char *)di + di_len);
2060                 }
2061         }
2062         if (key_type == BTRFS_DIR_INDEX_KEY)
2063                 filp->f_pos = INT_LIMIT(typeof(filp->f_pos));
2064         else
2065                 filp->f_pos++;
2066 nopos:
2067         ret = 0;
2068 err:
2069         btrfs_free_path(path);
2070         return ret;
2071 }
2072
2073 int btrfs_write_inode(struct inode *inode, int wait)
2074 {
2075         struct btrfs_root *root = BTRFS_I(inode)->root;
2076         struct btrfs_trans_handle *trans;
2077         int ret = 0;
2078
2079         if (wait) {
2080                 trans = btrfs_join_transaction(root, 1);
2081                 btrfs_set_trans_block_group(trans, inode);
2082                 ret = btrfs_commit_transaction(trans, root);
2083         }
2084         return ret;
2085 }
2086
2087 /*
2088  * This is somewhat expensive, updating the tree every time the
2089  * inode changes.  But, it is most likely to find the inode in cache.
2090  * FIXME, needs more benchmarking...there are no reasons other than performance
2091  * to keep or drop this code.
2092  */
2093 void btrfs_dirty_inode(struct inode *inode)
2094 {
2095         struct btrfs_root *root = BTRFS_I(inode)->root;
2096         struct btrfs_trans_handle *trans;
2097
2098         trans = btrfs_join_transaction(root, 1);
2099         btrfs_set_trans_block_group(trans, inode);
2100         btrfs_update_inode(trans, root, inode);
2101         btrfs_end_transaction(trans, root);
2102 }
2103
2104 static int btrfs_set_inode_index_count(struct inode *inode)
2105 {
2106         struct btrfs_root *root = BTRFS_I(inode)->root;
2107         struct btrfs_key key, found_key;
2108         struct btrfs_path *path;
2109         struct extent_buffer *leaf;
2110         int ret;
2111
2112         key.objectid = inode->i_ino;
2113         btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
2114         key.offset = (u64)-1;
2115
2116         path = btrfs_alloc_path();
2117         if (!path)
2118                 return -ENOMEM;
2119
2120         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2121         if (ret < 0)
2122                 goto out;
2123         /* FIXME: we should be able to handle this */
2124         if (ret == 0)
2125                 goto out;
2126         ret = 0;
2127
2128         /*
2129          * MAGIC NUMBER EXPLANATION:
2130          * since we search a directory based on f_pos we have to start at 2
2131          * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
2132          * else has to start at 2
2133          */
2134         if (path->slots[0] == 0) {
2135                 BTRFS_I(inode)->index_cnt = 2;
2136                 goto out;
2137         }
2138
2139         path->slots[0]--;
2140
2141         leaf = path->nodes[0];
2142         btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2143
2144         if (found_key.objectid != inode->i_ino ||
2145             btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
2146                 BTRFS_I(inode)->index_cnt = 2;
2147                 goto out;
2148         }
2149
2150         BTRFS_I(inode)->index_cnt = found_key.offset + 1;
2151 out:
2152         btrfs_free_path(path);
2153         return ret;
2154 }
2155
2156 static int btrfs_set_inode_index(struct inode *dir, struct inode *inode)
2157 {
2158         int ret = 0;
2159
2160         if (BTRFS_I(dir)->index_cnt == (u64)-1) {
2161                 ret = btrfs_set_inode_index_count(dir);
2162                 if (ret)
2163                         return ret;
2164         }
2165
2166         BTRFS_I(inode)->index = BTRFS_I(dir)->index_cnt;
2167         BTRFS_I(dir)->index_cnt++;
2168
2169         return ret;
2170 }
2171
2172 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
2173                                      struct btrfs_root *root,
2174                                      struct inode *dir,
2175                                      const char *name, int name_len,
2176                                      u64 ref_objectid,
2177                                      u64 objectid,
2178                                      struct btrfs_block_group_cache *group,
2179                                      int mode)
2180 {
2181         struct inode *inode;
2182         struct btrfs_inode_item *inode_item;
2183         struct btrfs_block_group_cache *new_inode_group;
2184         struct btrfs_key *location;
2185         struct btrfs_path *path;
2186         struct btrfs_inode_ref *ref;
2187         struct btrfs_key key[2];
2188         u32 sizes[2];
2189         unsigned long ptr;
2190         int ret;
2191         int owner;
2192
2193         path = btrfs_alloc_path();
2194         BUG_ON(!path);
2195
2196         inode = new_inode(root->fs_info->sb);
2197         if (!inode)
2198                 return ERR_PTR(-ENOMEM);
2199
2200         if (dir) {
2201                 ret = btrfs_set_inode_index(dir, inode);
2202                 if (ret)
2203                         return ERR_PTR(ret);
2204         } else {
2205                 BTRFS_I(inode)->index = 0;
2206         }
2207         /*
2208          * index_cnt is ignored for everything but a dir,
2209          * btrfs_get_inode_index_count has an explanation for the magic
2210          * number
2211          */
2212         BTRFS_I(inode)->index_cnt = 2;
2213
2214         extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
2215         extent_io_tree_init(&BTRFS_I(inode)->io_tree,
2216                              inode->i_mapping, GFP_NOFS);
2217         extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
2218                              inode->i_mapping, GFP_NOFS);
2219         btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
2220         INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
2221         mutex_init(&BTRFS_I(inode)->csum_mutex);
2222         mutex_init(&BTRFS_I(inode)->extent_mutex);
2223         BTRFS_I(inode)->delalloc_bytes = 0;
2224         BTRFS_I(inode)->disk_i_size = 0;
2225         BTRFS_I(inode)->root = root;
2226
2227         if (mode & S_IFDIR)
2228                 owner = 0;
2229         else
2230                 owner = 1;
2231         new_inode_group = btrfs_find_block_group(root, group, 0,
2232                                        BTRFS_BLOCK_GROUP_METADATA, owner);
2233         if (!new_inode_group) {
2234                 printk("find_block group failed\n");
2235                 new_inode_group = group;
2236         }
2237         BTRFS_I(inode)->block_group = new_inode_group;
2238         BTRFS_I(inode)->flags = 0;
2239
2240         key[0].objectid = objectid;
2241         btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
2242         key[0].offset = 0;
2243
2244         key[1].objectid = objectid;
2245         btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
2246         key[1].offset = ref_objectid;
2247
2248         sizes[0] = sizeof(struct btrfs_inode_item);
2249         sizes[1] = name_len + sizeof(*ref);
2250
2251         ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
2252         if (ret != 0)
2253                 goto fail;
2254
2255         if (objectid > root->highest_inode)
2256                 root->highest_inode = objectid;
2257
2258         inode->i_uid = current->fsuid;
2259         inode->i_gid = current->fsgid;
2260         inode->i_mode = mode;
2261         inode->i_ino = objectid;
2262         inode->i_blocks = 0;
2263         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2264         inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
2265                                   struct btrfs_inode_item);
2266         fill_inode_item(path->nodes[0], inode_item, inode);
2267
2268         ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
2269                              struct btrfs_inode_ref);
2270         btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
2271         btrfs_set_inode_ref_index(path->nodes[0], ref, BTRFS_I(inode)->index);
2272         ptr = (unsigned long)(ref + 1);
2273         write_extent_buffer(path->nodes[0], name, ptr, name_len);
2274
2275         btrfs_mark_buffer_dirty(path->nodes[0]);
2276         btrfs_free_path(path);
2277
2278         location = &BTRFS_I(inode)->location;
2279         location->objectid = objectid;
2280         location->offset = 0;
2281         btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
2282
2283         insert_inode_hash(inode);
2284         return inode;
2285 fail:
2286         if (dir)
2287                 BTRFS_I(dir)->index_cnt--;
2288         btrfs_free_path(path);
2289         return ERR_PTR(ret);
2290 }
2291
2292 static inline u8 btrfs_inode_type(struct inode *inode)
2293 {
2294         return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
2295 }
2296
2297 static int btrfs_add_link(struct btrfs_trans_handle *trans,
2298                             struct dentry *dentry, struct inode *inode,
2299                             int add_backref)
2300 {
2301         int ret;
2302         struct btrfs_key key;
2303         struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
2304         struct inode *parent_inode = dentry->d_parent->d_inode;
2305
2306         key.objectid = inode->i_ino;
2307         btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
2308         key.offset = 0;
2309
2310         ret = btrfs_insert_dir_item(trans, root,
2311                                     dentry->d_name.name, dentry->d_name.len,
2312                                     dentry->d_parent->d_inode->i_ino,
2313                                     &key, btrfs_inode_type(inode),
2314                                     BTRFS_I(inode)->index);
2315         if (ret == 0) {
2316                 if (add_backref) {
2317                         ret = btrfs_insert_inode_ref(trans, root,
2318                                              dentry->d_name.name,
2319                                              dentry->d_name.len,
2320                                              inode->i_ino,
2321                                              parent_inode->i_ino,
2322                                              BTRFS_I(inode)->index);
2323                 }
2324                 btrfs_i_size_write(parent_inode, parent_inode->i_size +
2325                                    dentry->d_name.len * 2);
2326                 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
2327                 ret = btrfs_update_inode(trans, root,
2328                                          dentry->d_parent->d_inode);
2329         }
2330         return ret;
2331 }
2332
2333 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
2334                             struct dentry *dentry, struct inode *inode,
2335                             int backref)
2336 {
2337         int err = btrfs_add_link(trans, dentry, inode, backref);
2338         if (!err) {
2339                 d_instantiate(dentry, inode);
2340                 return 0;
2341         }
2342         if (err > 0)
2343                 err = -EEXIST;
2344         return err;
2345 }
2346
2347 static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
2348                         int mode, dev_t rdev)
2349 {
2350         struct btrfs_trans_handle *trans;
2351         struct btrfs_root *root = BTRFS_I(dir)->root;
2352         struct inode *inode = NULL;
2353         int err;
2354         int drop_inode = 0;
2355         u64 objectid;
2356         unsigned long nr = 0;
2357
2358         if (!new_valid_dev(rdev))
2359                 return -EINVAL;
2360
2361         err = btrfs_check_free_space(root, 1, 0);
2362         if (err)
2363                 goto fail;
2364
2365         trans = btrfs_start_transaction(root, 1);
2366         btrfs_set_trans_block_group(trans, dir);
2367
2368         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2369         if (err) {
2370                 err = -ENOSPC;
2371                 goto out_unlock;
2372         }
2373
2374         inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2375                                 dentry->d_name.len,
2376                                 dentry->d_parent->d_inode->i_ino, objectid,
2377                                 BTRFS_I(dir)->block_group, mode);
2378         err = PTR_ERR(inode);
2379         if (IS_ERR(inode))
2380                 goto out_unlock;
2381
2382         err = btrfs_init_acl(inode, dir);
2383         if (err) {
2384                 drop_inode = 1;
2385                 goto out_unlock;
2386         }
2387
2388         btrfs_set_trans_block_group(trans, inode);
2389         err = btrfs_add_nondir(trans, dentry, inode, 0);
2390         if (err)
2391                 drop_inode = 1;
2392         else {
2393                 inode->i_op = &btrfs_special_inode_operations;
2394                 init_special_inode(inode, inode->i_mode, rdev);
2395                 btrfs_update_inode(trans, root, inode);
2396         }
2397         dir->i_sb->s_dirt = 1;
2398         btrfs_update_inode_block_group(trans, inode);
2399         btrfs_update_inode_block_group(trans, dir);
2400 out_unlock:
2401         nr = trans->blocks_used;
2402         btrfs_end_transaction_throttle(trans, root);
2403 fail:
2404         if (drop_inode) {
2405                 inode_dec_link_count(inode);
2406                 iput(inode);
2407         }
2408         btrfs_btree_balance_dirty(root, nr);
2409         return err;
2410 }
2411
2412 static int btrfs_create(struct inode *dir, struct dentry *dentry,
2413                         int mode, struct nameidata *nd)
2414 {
2415         struct btrfs_trans_handle *trans;
2416         struct btrfs_root *root = BTRFS_I(dir)->root;
2417         struct inode *inode = NULL;
2418         int err;
2419         int drop_inode = 0;
2420         unsigned long nr = 0;
2421         u64 objectid;
2422
2423         err = btrfs_check_free_space(root, 1, 0);
2424         if (err)
2425                 goto fail;
2426         trans = btrfs_start_transaction(root, 1);
2427         btrfs_set_trans_block_group(trans, dir);
2428
2429         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2430         if (err) {
2431                 err = -ENOSPC;
2432                 goto out_unlock;
2433         }
2434
2435         inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2436                                 dentry->d_name.len,
2437                                 dentry->d_parent->d_inode->i_ino,
2438                                 objectid, BTRFS_I(dir)->block_group, mode);
2439         err = PTR_ERR(inode);
2440         if (IS_ERR(inode))
2441                 goto out_unlock;
2442
2443         err = btrfs_init_acl(inode, dir);
2444         if (err) {
2445                 drop_inode = 1;
2446                 goto out_unlock;
2447         }
2448
2449         btrfs_set_trans_block_group(trans, inode);
2450         err = btrfs_add_nondir(trans, dentry, inode, 0);
2451         if (err)
2452                 drop_inode = 1;
2453         else {
2454                 inode->i_mapping->a_ops = &btrfs_aops;
2455                 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
2456                 inode->i_fop = &btrfs_file_operations;
2457                 inode->i_op = &btrfs_file_inode_operations;
2458                 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
2459                 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
2460                                      inode->i_mapping, GFP_NOFS);
2461                 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
2462                                      inode->i_mapping, GFP_NOFS);
2463                 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
2464                 mutex_init(&BTRFS_I(inode)->csum_mutex);
2465                 mutex_init(&BTRFS_I(inode)->extent_mutex);
2466                 BTRFS_I(inode)->delalloc_bytes = 0;
2467                 BTRFS_I(inode)->disk_i_size = 0;
2468                 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
2469                 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
2470         }
2471         dir->i_sb->s_dirt = 1;
2472         btrfs_update_inode_block_group(trans, inode);
2473         btrfs_update_inode_block_group(trans, dir);
2474 out_unlock:
2475         nr = trans->blocks_used;
2476         btrfs_end_transaction_throttle(trans, root);
2477 fail:
2478         if (drop_inode) {
2479                 inode_dec_link_count(inode);
2480                 iput(inode);
2481         }
2482         btrfs_btree_balance_dirty(root, nr);
2483         return err;
2484 }
2485
2486 static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
2487                       struct dentry *dentry)
2488 {
2489         struct btrfs_trans_handle *trans;
2490         struct btrfs_root *root = BTRFS_I(dir)->root;
2491         struct inode *inode = old_dentry->d_inode;
2492         unsigned long nr = 0;
2493         int err;
2494         int drop_inode = 0;
2495
2496         if (inode->i_nlink == 0)
2497                 return -ENOENT;
2498
2499 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
2500         inode->i_nlink++;
2501 #else
2502         inc_nlink(inode);
2503 #endif
2504         err = btrfs_check_free_space(root, 1, 0);
2505         if (err)
2506                 goto fail;
2507         err = btrfs_set_inode_index(dir, inode);
2508         if (err)
2509                 goto fail;
2510
2511         trans = btrfs_start_transaction(root, 1);
2512
2513         btrfs_set_trans_block_group(trans, dir);
2514         atomic_inc(&inode->i_count);
2515
2516         err = btrfs_add_nondir(trans, dentry, inode, 1);
2517
2518         if (err)
2519                 drop_inode = 1;
2520
2521         dir->i_sb->s_dirt = 1;
2522         btrfs_update_inode_block_group(trans, dir);
2523         err = btrfs_update_inode(trans, root, inode);
2524
2525         if (err)
2526                 drop_inode = 1;
2527
2528         nr = trans->blocks_used;
2529         btrfs_end_transaction_throttle(trans, root);
2530 fail:
2531         if (drop_inode) {
2532                 inode_dec_link_count(inode);
2533                 iput(inode);
2534         }
2535         btrfs_btree_balance_dirty(root, nr);
2536         return err;
2537 }
2538
2539 static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
2540 {
2541         struct inode *inode = NULL;
2542         struct btrfs_trans_handle *trans;
2543         struct btrfs_root *root = BTRFS_I(dir)->root;
2544         int err = 0;
2545         int drop_on_err = 0;
2546         u64 objectid = 0;
2547         unsigned long nr = 1;
2548
2549         err = btrfs_check_free_space(root, 1, 0);
2550         if (err)
2551                 goto out_unlock;
2552
2553         trans = btrfs_start_transaction(root, 1);
2554         btrfs_set_trans_block_group(trans, dir);
2555
2556         if (IS_ERR(trans)) {
2557                 err = PTR_ERR(trans);
2558                 goto out_unlock;
2559         }
2560
2561         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
2562         if (err) {
2563                 err = -ENOSPC;
2564                 goto out_unlock;
2565         }
2566
2567         inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
2568                                 dentry->d_name.len,
2569                                 dentry->d_parent->d_inode->i_ino, objectid,
2570                                 BTRFS_I(dir)->block_group, S_IFDIR | mode);
2571         if (IS_ERR(inode)) {
2572                 err = PTR_ERR(inode);
2573                 goto out_fail;
2574         }
2575
2576         drop_on_err = 1;
2577
2578         err = btrfs_init_acl(inode, dir);
2579         if (err)
2580                 goto out_fail;
2581
2582         inode->i_op = &btrfs_dir_inode_operations;
2583         inode->i_fop = &btrfs_dir_file_operations;
2584         btrfs_set_trans_block_group(trans, inode);
2585
2586         btrfs_i_size_write(inode, 0);
2587         err = btrfs_update_inode(trans, root, inode);
2588         if (err)
2589                 goto out_fail;
2590
2591         err = btrfs_add_link(trans, dentry, inode, 0);
2592         if (err)
2593                 goto out_fail;
2594
2595         d_instantiate(dentry, inode);
2596         drop_on_err = 0;
2597         dir->i_sb->s_dirt = 1;
2598         btrfs_update_inode_block_group(trans, inode);
2599         btrfs_update_inode_block_group(trans, dir);
2600
2601 out_fail:
2602         nr = trans->blocks_used;
2603         btrfs_end_transaction_throttle(trans, root);
2604
2605 out_unlock:
2606         if (drop_on_err)
2607                 iput(inode);
2608         btrfs_btree_balance_dirty(root, nr);
2609         return err;
2610 }
2611
2612 static int merge_extent_mapping(struct extent_map_tree *em_tree,
2613                                 struct extent_map *existing,
2614                                 struct extent_map *em,
2615                                 u64 map_start, u64 map_len)
2616 {
2617         u64 start_diff;
2618
2619         BUG_ON(map_start < em->start || map_start >= extent_map_end(em));
2620         start_diff = map_start - em->start;
2621         em->start = map_start;
2622         em->len = map_len;
2623         if (em->block_start < EXTENT_MAP_LAST_BYTE)
2624                 em->block_start += start_diff;
2625         return add_extent_mapping(em_tree, em);
2626 }
2627
2628 struct extent_map *btrfs_get_extent(struct inode *inode, struct page *page,
2629                                     size_t pg_offset, u64 start, u64 len,
2630                                     int create)
2631 {
2632         int ret;
2633         int err = 0;
2634         u64 bytenr;
2635         u64 extent_start = 0;
2636         u64 extent_end = 0;
2637         u64 objectid = inode->i_ino;
2638         u32 found_type;
2639         struct btrfs_path *path = NULL;
2640         struct btrfs_root *root = BTRFS_I(inode)->root;
2641         struct btrfs_file_extent_item *item;
2642         struct extent_buffer *leaf;
2643         struct btrfs_key found_key;
2644         struct extent_map *em = NULL;
2645         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
2646         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
2647         struct btrfs_trans_handle *trans = NULL;
2648
2649 again:
2650         spin_lock(&em_tree->lock);
2651         em = lookup_extent_mapping(em_tree, start, len);
2652         if (em)
2653                 em->bdev = root->fs_info->fs_devices->latest_bdev;
2654         spin_unlock(&em_tree->lock);
2655
2656         if (em) {
2657                 if (em->start > start || em->start + em->len <= start)
2658                         free_extent_map(em);
2659                 else if (em->block_start == EXTENT_MAP_INLINE && page)
2660                         free_extent_map(em);
2661                 else
2662                         goto out;
2663         }
2664         em = alloc_extent_map(GFP_NOFS);
2665         if (!em) {
2666                 err = -ENOMEM;
2667                 goto out;
2668         }
2669         em->bdev = root->fs_info->fs_devices->latest_bdev;
2670         em->start = EXTENT_MAP_HOLE;
2671         em->len = (u64)-1;
2672
2673         if (!path) {
2674                 path = btrfs_alloc_path();
2675                 BUG_ON(!path);
2676         }
2677
2678         ret = btrfs_lookup_file_extent(trans, root, path,
2679                                        objectid, start, trans != NULL);
2680         if (ret < 0) {
2681                 err = ret;
2682                 goto out;
2683         }
2684
2685         if (ret != 0) {
2686                 if (path->slots[0] == 0)
2687                         goto not_found;
2688                 path->slots[0]--;
2689         }
2690
2691         leaf = path->nodes[0];
2692         item = btrfs_item_ptr(leaf, path->slots[0],
2693                               struct btrfs_file_extent_item);
2694         /* are we inside the extent that was found? */
2695         btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
2696         found_type = btrfs_key_type(&found_key);
2697         if (found_key.objectid != objectid ||
2698             found_type != BTRFS_EXTENT_DATA_KEY) {
2699                 goto not_found;
2700         }
2701
2702         found_type = btrfs_file_extent_type(leaf, item);
2703         extent_start = found_key.offset;
2704         if (found_type == BTRFS_FILE_EXTENT_REG) {
2705                 extent_end = extent_start +
2706                        btrfs_file_extent_num_bytes(leaf, item);
2707                 err = 0;
2708                 if (start < extent_start || start >= extent_end) {
2709                         em->start = start;
2710                         if (start < extent_start) {
2711                                 if (start + len <= extent_start)
2712                                         goto not_found;
2713                                 em->len = extent_end - extent_start;
2714                         } else {
2715                                 em->len = len;
2716                         }
2717                         goto not_found_em;
2718                 }
2719                 bytenr = btrfs_file_extent_disk_bytenr(leaf, item);
2720                 if (bytenr == 0) {
2721                         em->start = extent_start;
2722                         em->len = extent_end - extent_start;
2723                         em->block_start = EXTENT_MAP_HOLE;
2724                         goto insert;
2725                 }
2726                 bytenr += btrfs_file_extent_offset(leaf, item);
2727                 em->block_start = bytenr;
2728                 em->start = extent_start;
2729                 em->len = extent_end - extent_start;
2730                 goto insert;
2731         } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
2732                 u64 page_start;
2733                 unsigned long ptr;
2734                 char *map;
2735                 size_t size;
2736                 size_t extent_offset;
2737                 size_t copy_size;
2738
2739                 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
2740                                                     path->slots[0]));
2741                 extent_end = (extent_start + size + root->sectorsize - 1) &
2742                         ~((u64)root->sectorsize - 1);
2743                 if (start < extent_start || start >= extent_end) {
2744                         em->start = start;
2745                         if (start < extent_start) {
2746                                 if (start + len <= extent_start)
2747                                         goto not_found;
2748                                 em->len = extent_end - extent_start;
2749                         } else {
2750                                 em->len = len;
2751                         }
2752                         goto not_found_em;
2753                 }
2754                 em->block_start = EXTENT_MAP_INLINE;
2755
2756                 if (!page) {
2757                         em->start = extent_start;
2758                         em->len = size;
2759                         goto out;
2760                 }
2761
2762                 page_start = page_offset(page) + pg_offset;
2763                 extent_offset = page_start - extent_start;
2764                 copy_size = min_t(u64, PAGE_CACHE_SIZE - pg_offset,
2765                                 size - extent_offset);
2766                 em->start = extent_start + extent_offset;
2767                 em->len = (copy_size + root->sectorsize - 1) &
2768                         ~((u64)root->sectorsize - 1);
2769                 map = kmap(page);
2770                 ptr = btrfs_file_extent_inline_start(item) + extent_offset;
2771                 if (create == 0 && !PageUptodate(page)) {
2772                         read_extent_buffer(leaf, map + pg_offset, ptr,
2773                                            copy_size);
2774                         flush_dcache_page(page);
2775                 } else if (create && PageUptodate(page)) {
2776                         if (!trans) {
2777                                 kunmap(page);
2778                                 free_extent_map(em);
2779                                 em = NULL;
2780                                 btrfs_release_path(root, path);
2781                                 trans = btrfs_join_transaction(root, 1);
2782                                 goto again;
2783                         }
2784                         write_extent_buffer(leaf, map + pg_offset, ptr,
2785                                             copy_size);
2786                         btrfs_mark_buffer_dirty(leaf);
2787                 }
2788                 kunmap(page);
2789                 set_extent_uptodate(io_tree, em->start,
2790                                     extent_map_end(em) - 1, GFP_NOFS);
2791                 goto insert;
2792         } else {
2793                 printk("unkknown found_type %d\n", found_type);
2794                 WARN_ON(1);
2795         }
2796 not_found:
2797         em->start = start;
2798         em->len = len;
2799 not_found_em:
2800         em->block_start = EXTENT_MAP_HOLE;
2801 insert:
2802         btrfs_release_path(root, path);
2803         if (em->start > start || extent_map_end(em) <= start) {
2804                 printk("bad extent! em: [%Lu %Lu] passed [%Lu %Lu]\n", em->start, em->len, start, len);
2805                 err = -EIO;
2806                 goto out;
2807         }
2808
2809         err = 0;
2810         spin_lock(&em_tree->lock);
2811         ret = add_extent_mapping(em_tree, em);
2812         /* it is possible that someone inserted the extent into the tree
2813          * while we had the lock dropped.  It is also possible that
2814          * an overlapping map exists in the tree
2815          */
2816         if (ret == -EEXIST) {
2817                 struct extent_map *existing;
2818
2819                 ret = 0;
2820
2821                 existing = lookup_extent_mapping(em_tree, start, len);
2822                 if (existing && (existing->start > start ||
2823                     existing->start + existing->len <= start)) {
2824                         free_extent_map(existing);
2825                         existing = NULL;
2826                 }
2827                 if (!existing) {
2828                         existing = lookup_extent_mapping(em_tree, em->start,
2829                                                          em->len);
2830                         if (existing) {
2831                                 err = merge_extent_mapping(em_tree, existing,
2832                                                            em, start,
2833                                                            root->sectorsize);
2834                                 free_extent_map(existing);
2835                                 if (err) {
2836                                         free_extent_map(em);
2837                                         em = NULL;
2838                                 }
2839                         } else {
2840                                 err = -EIO;
2841                                 printk("failing to insert %Lu %Lu\n",
2842                                        start, len);
2843                                 free_extent_map(em);
2844                                 em = NULL;
2845                         }
2846                 } else {
2847                         free_extent_map(em);
2848                         em = existing;
2849                         err = 0;
2850                 }
2851         }
2852         spin_unlock(&em_tree->lock);
2853 out:
2854         if (path)
2855                 btrfs_free_path(path);
2856         if (trans) {
2857                 ret = btrfs_end_transaction(trans, root);
2858                 if (!err) {
2859                         err = ret;
2860                 }
2861         }
2862         if (err) {
2863                 free_extent_map(em);
2864                 WARN_ON(1);
2865                 return ERR_PTR(err);
2866         }
2867         return em;
2868 }
2869
2870 #if 0 /* waiting for O_DIRECT reads */
2871 static int btrfs_get_block(struct inode *inode, sector_t iblock,
2872                         struct buffer_head *bh_result, int create)
2873 {
2874         struct extent_map *em;
2875         u64 start = (u64)iblock << inode->i_blkbits;
2876         struct btrfs_multi_bio *multi = NULL;
2877         struct btrfs_root *root = BTRFS_I(inode)->root;
2878         u64 len;
2879         u64 logical;
2880         u64 map_length;
2881         int ret = 0;
2882
2883         em = btrfs_get_extent(inode, NULL, 0, start, bh_result->b_size, 0);
2884
2885         if (!em || IS_ERR(em))
2886                 goto out;
2887
2888         if (em->start > start || em->start + em->len <= start) {
2889             goto out;
2890         }
2891
2892         if (em->block_start == EXTENT_MAP_INLINE) {
2893                 ret = -EINVAL;
2894                 goto out;
2895         }
2896
2897         len = em->start + em->len - start;
2898         len = min_t(u64, len, INT_LIMIT(typeof(bh_result->b_size)));
2899
2900         if (em->block_start == EXTENT_MAP_HOLE ||
2901             em->block_start == EXTENT_MAP_DELALLOC) {
2902                 bh_result->b_size = len;
2903                 goto out;
2904         }
2905
2906         logical = start - em->start;
2907         logical = em->block_start + logical;
2908
2909         map_length = len;
2910         ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
2911                               logical, &map_length, &multi, 0);
2912         BUG_ON(ret);
2913         bh_result->b_blocknr = multi->stripes[0].physical >> inode->i_blkbits;
2914         bh_result->b_size = min(map_length, len);
2915
2916         bh_result->b_bdev = multi->stripes[0].dev->bdev;
2917         set_buffer_mapped(bh_result);
2918         kfree(multi);
2919 out:
2920         free_extent_map(em);
2921         return ret;
2922 }
2923 #endif
2924
2925 static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
2926                         const struct iovec *iov, loff_t offset,
2927                         unsigned long nr_segs)
2928 {
2929         return -EINVAL;
2930 #if 0
2931         struct file *file = iocb->ki_filp;
2932         struct inode *inode = file->f_mapping->host;
2933
2934         if (rw == WRITE)
2935                 return -EINVAL;
2936
2937         return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
2938                                   offset, nr_segs, btrfs_get_block, NULL);
2939 #endif
2940 }
2941
2942 static sector_t btrfs_bmap(struct address_space *mapping, sector_t iblock)
2943 {
2944         return extent_bmap(mapping, iblock, btrfs_get_extent);
2945 }
2946
2947 int btrfs_readpage(struct file *file, struct page *page)
2948 {
2949         struct extent_io_tree *tree;
2950         tree = &BTRFS_I(page->mapping->host)->io_tree;
2951         return extent_read_full_page(tree, page, btrfs_get_extent);
2952 }
2953
2954 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
2955 {
2956         struct extent_io_tree *tree;
2957
2958
2959         if (current->flags & PF_MEMALLOC) {
2960                 redirty_page_for_writepage(wbc, page);
2961                 unlock_page(page);
2962                 return 0;
2963         }
2964         tree = &BTRFS_I(page->mapping->host)->io_tree;
2965         return extent_write_full_page(tree, page, btrfs_get_extent, wbc);
2966 }
2967
2968 int btrfs_writepages(struct address_space *mapping,
2969                      struct writeback_control *wbc)
2970 {
2971         struct extent_io_tree *tree;
2972         tree = &BTRFS_I(mapping->host)->io_tree;
2973         return extent_writepages(tree, mapping, btrfs_get_extent, wbc);
2974 }
2975
2976 static int
2977 btrfs_readpages(struct file *file, struct address_space *mapping,
2978                 struct list_head *pages, unsigned nr_pages)
2979 {
2980         struct extent_io_tree *tree;
2981         tree = &BTRFS_I(mapping->host)->io_tree;
2982         return extent_readpages(tree, mapping, pages, nr_pages,
2983                                 btrfs_get_extent);
2984 }
2985 static int __btrfs_releasepage(struct page *page, gfp_t gfp_flags)
2986 {
2987         struct extent_io_tree *tree;
2988         struct extent_map_tree *map;
2989         int ret;
2990
2991         tree = &BTRFS_I(page->mapping->host)->io_tree;
2992         map = &BTRFS_I(page->mapping->host)->extent_tree;
2993         ret = try_release_extent_mapping(map, tree, page, gfp_flags);
2994         if (ret == 1) {
2995                 ClearPagePrivate(page);
2996                 set_page_private(page, 0);
2997                 page_cache_release(page);
2998         }
2999         return ret;
3000 }
3001
3002 static int btrfs_releasepage(struct page *page, gfp_t gfp_flags)
3003 {
3004         return __btrfs_releasepage(page, gfp_flags);
3005 }
3006
3007 static void btrfs_invalidatepage(struct page *page, unsigned long offset)
3008 {
3009         struct extent_io_tree *tree;
3010         struct btrfs_ordered_extent *ordered;
3011         u64 page_start = page_offset(page);
3012         u64 page_end = page_start + PAGE_CACHE_SIZE - 1;
3013
3014         wait_on_page_writeback(page);
3015         tree = &BTRFS_I(page->mapping->host)->io_tree;
3016         if (offset) {
3017                 btrfs_releasepage(page, GFP_NOFS);
3018                 return;
3019         }
3020
3021         lock_extent(tree, page_start, page_end, GFP_NOFS);
3022         ordered = btrfs_lookup_ordered_extent(page->mapping->host,
3023                                            page_offset(page));
3024         if (ordered) {
3025                 /*
3026                  * IO on this page will never be started, so we need
3027                  * to account for any ordered extents now
3028                  */
3029                 clear_extent_bit(tree, page_start, page_end,
3030                                  EXTENT_DIRTY | EXTENT_DELALLOC |
3031                                  EXTENT_LOCKED, 1, 0, GFP_NOFS);
3032                 btrfs_finish_ordered_io(page->mapping->host,
3033                                         page_start, page_end);
3034                 btrfs_put_ordered_extent(ordered);
3035                 lock_extent(tree, page_start, page_end, GFP_NOFS);
3036         }
3037         clear_extent_bit(tree, page_start, page_end,
3038                  EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
3039                  EXTENT_ORDERED,
3040                  1, 1, GFP_NOFS);
3041         __btrfs_releasepage(page, GFP_NOFS);
3042
3043         ClearPageChecked(page);
3044         if (PagePrivate(page)) {
3045                 ClearPagePrivate(page);
3046                 set_page_private(page, 0);
3047                 page_cache_release(page);
3048         }
3049 }
3050
3051 /*
3052  * btrfs_page_mkwrite() is not allowed to change the file size as it gets
3053  * called from a page fault handler when a page is first dirtied. Hence we must
3054  * be careful to check for EOF conditions here. We set the page up correctly
3055  * for a written page which means we get ENOSPC checking when writing into
3056  * holes and correct delalloc and unwritten extent mapping on filesystems that
3057  * support these features.
3058  *
3059  * We are not allowed to take the i_mutex here so we have to play games to
3060  * protect against truncate races as the page could now be beyond EOF.  Because
3061  * vmtruncate() writes the inode size before removing pages, once we have the
3062  * page lock we can determine safely if the page is beyond EOF. If it is not
3063  * beyond EOF, then the page is guaranteed safe against truncation until we
3064  * unlock the page.
3065  */
3066 int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
3067 {
3068         struct inode *inode = fdentry(vma->vm_file)->d_inode;
3069         struct btrfs_root *root = BTRFS_I(inode)->root;
3070         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
3071         struct btrfs_ordered_extent *ordered;
3072         char *kaddr;
3073         unsigned long zero_start;
3074         loff_t size;
3075         int ret;
3076         u64 page_start;
3077         u64 page_end;
3078
3079         ret = btrfs_check_free_space(root, PAGE_CACHE_SIZE, 0);
3080         if (ret)
3081                 goto out;
3082
3083         ret = -EINVAL;
3084 again:
3085         lock_page(page);
3086         size = i_size_read(inode);
3087         page_start = page_offset(page);
3088         page_end = page_start + PAGE_CACHE_SIZE - 1;
3089
3090         if ((page->mapping != inode->i_mapping) ||
3091             (page_start >= size)) {
3092                 /* page got truncated out from underneath us */
3093                 goto out_unlock;
3094         }
3095         wait_on_page_writeback(page);
3096
3097         lock_extent(io_tree, page_start, page_end, GFP_NOFS);
3098         set_page_extent_mapped(page);
3099
3100         /*
3101          * we can't set the delalloc bits if there are pending ordered
3102          * extents.  Drop our locks and wait for them to finish
3103          */
3104         ordered = btrfs_lookup_ordered_extent(inode, page_start);
3105         if (ordered) {
3106                 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3107                 unlock_page(page);
3108                 btrfs_start_ordered_extent(inode, ordered, 1);
3109                 btrfs_put_ordered_extent(ordered);
3110                 goto again;
3111         }
3112
3113         btrfs_set_extent_delalloc(inode, page_start, page_end);
3114         ret = 0;
3115
3116         /* page is wholly or partially inside EOF */
3117         if (page_start + PAGE_CACHE_SIZE > size)
3118                 zero_start = size & ~PAGE_CACHE_MASK;
3119         else
3120                 zero_start = PAGE_CACHE_SIZE;
3121
3122         if (zero_start != PAGE_CACHE_SIZE) {
3123                 kaddr = kmap(page);
3124                 memset(kaddr + zero_start, 0, PAGE_CACHE_SIZE - zero_start);
3125                 flush_dcache_page(page);
3126                 kunmap(page);
3127         }
3128         ClearPageChecked(page);
3129         set_page_dirty(page);
3130         unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
3131
3132 out_unlock:
3133         unlock_page(page);
3134 out:
3135         return ret;
3136 }
3137
3138 static void btrfs_truncate(struct inode *inode)
3139 {
3140         struct btrfs_root *root = BTRFS_I(inode)->root;
3141         int ret;
3142         struct btrfs_trans_handle *trans;
3143         unsigned long nr;
3144         u64 mask = root->sectorsize - 1;
3145
3146         if (!S_ISREG(inode->i_mode))
3147                 return;
3148         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
3149                 return;
3150
3151         btrfs_truncate_page(inode->i_mapping, inode->i_size);
3152         btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
3153
3154         trans = btrfs_start_transaction(root, 1);
3155         btrfs_set_trans_block_group(trans, inode);
3156         btrfs_i_size_write(inode, inode->i_size);
3157
3158         ret = btrfs_orphan_add(trans, inode);
3159         if (ret)
3160                 goto out;
3161         /* FIXME, add redo link to tree so we don't leak on crash */
3162         ret = btrfs_truncate_in_trans(trans, root, inode,
3163                                       BTRFS_EXTENT_DATA_KEY);
3164         btrfs_update_inode(trans, root, inode);
3165
3166         ret = btrfs_orphan_del(trans, inode);
3167         BUG_ON(ret);
3168
3169 out:
3170         nr = trans->blocks_used;
3171         ret = btrfs_end_transaction_throttle(trans, root);
3172         BUG_ON(ret);
3173         btrfs_btree_balance_dirty(root, nr);
3174 }
3175
3176 /*
3177  * Invalidate a single dcache entry at the root of the filesystem.
3178  * Needed after creation of snapshot or subvolume.
3179  */
3180 void btrfs_invalidate_dcache_root(struct btrfs_root *root, char *name,
3181                                   int namelen)
3182 {
3183         struct dentry *alias, *entry;
3184         struct qstr qstr;
3185
3186         alias = d_find_alias(root->fs_info->sb->s_root->d_inode);
3187         if (alias) {
3188                 qstr.name = name;
3189                 qstr.len = namelen;
3190                 /* change me if btrfs ever gets a d_hash operation */
3191                 qstr.hash = full_name_hash(qstr.name, qstr.len);
3192                 entry = d_lookup(alias, &qstr);
3193                 dput(alias);
3194                 if (entry) {
3195                         d_invalidate(entry);
3196                         dput(entry);
3197                 }
3198         }
3199 }
3200
3201 int btrfs_create_subvol_root(struct btrfs_root *new_root,
3202                 struct btrfs_trans_handle *trans, u64 new_dirid,
3203                 struct btrfs_block_group_cache *block_group)
3204 {
3205         struct inode *inode;
3206
3207         inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
3208                                 new_dirid, block_group, S_IFDIR | 0700);
3209         if (IS_ERR(inode))
3210                 return PTR_ERR(inode);
3211         inode->i_op = &btrfs_dir_inode_operations;
3212         inode->i_fop = &btrfs_dir_file_operations;
3213         new_root->inode = inode;
3214
3215         inode->i_nlink = 1;
3216         btrfs_i_size_write(inode, 0);
3217
3218         return btrfs_update_inode(trans, new_root, inode);
3219 }
3220
3221 unsigned long btrfs_force_ra(struct address_space *mapping,
3222                               struct file_ra_state *ra, struct file *file,
3223                               pgoff_t offset, pgoff_t last_index)
3224 {
3225         pgoff_t req_size = last_index - offset + 1;
3226
3227 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
3228         offset = page_cache_readahead(mapping, ra, file, offset, req_size);
3229         return offset;
3230 #else
3231         page_cache_sync_readahead(mapping, ra, file, offset, req_size);
3232         return offset + req_size;
3233 #endif
3234 }
3235
3236 struct inode *btrfs_alloc_inode(struct super_block *sb)
3237 {
3238         struct btrfs_inode *ei;
3239
3240         ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
3241         if (!ei)
3242                 return NULL;
3243         ei->last_trans = 0;
3244         btrfs_ordered_inode_tree_init(&ei->ordered_tree);
3245         ei->i_acl = BTRFS_ACL_NOT_CACHED;
3246         ei->i_default_acl = BTRFS_ACL_NOT_CACHED;
3247         INIT_LIST_HEAD(&ei->i_orphan);
3248         return &ei->vfs_inode;
3249 }
3250
3251 void btrfs_destroy_inode(struct inode *inode)
3252 {
3253         struct btrfs_ordered_extent *ordered;
3254         WARN_ON(!list_empty(&inode->i_dentry));
3255         WARN_ON(inode->i_data.nrpages);
3256
3257         if (BTRFS_I(inode)->i_acl &&
3258             BTRFS_I(inode)->i_acl != BTRFS_ACL_NOT_CACHED)
3259                 posix_acl_release(BTRFS_I(inode)->i_acl);
3260         if (BTRFS_I(inode)->i_default_acl &&
3261             BTRFS_I(inode)->i_default_acl != BTRFS_ACL_NOT_CACHED)
3262                 posix_acl_release(BTRFS_I(inode)->i_default_acl);
3263
3264         spin_lock(&BTRFS_I(inode)->root->list_lock);
3265         if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
3266                 printk(KERN_ERR "BTRFS: inode %lu: inode still on the orphan"
3267                        " list\n", inode->i_ino);
3268                 dump_stack();
3269         }
3270         spin_unlock(&BTRFS_I(inode)->root->list_lock);
3271
3272         while(1) {
3273                 ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
3274                 if (!ordered)
3275                         break;
3276                 else {
3277                         printk("found ordered extent %Lu %Lu\n",
3278                                ordered->file_offset, ordered->len);
3279                         btrfs_remove_ordered_extent(inode, ordered);
3280                         btrfs_put_ordered_extent(ordered);
3281                         btrfs_put_ordered_extent(ordered);
3282                 }
3283         }
3284         btrfs_drop_extent_cache(inode, 0, (u64)-1);
3285         kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
3286 }
3287
3288 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3289 static void init_once(void *foo)
3290 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
3291 static void init_once(struct kmem_cache * cachep, void *foo)
3292 #else
3293 static void init_once(void * foo, struct kmem_cache * cachep,
3294                       unsigned long flags)
3295 #endif
3296 {
3297         struct btrfs_inode *ei = (struct btrfs_inode *) foo;
3298
3299         inode_init_once(&ei->vfs_inode);
3300 }
3301
3302 void btrfs_destroy_cachep(void)
3303 {
3304         if (btrfs_inode_cachep)
3305                 kmem_cache_destroy(btrfs_inode_cachep);
3306         if (btrfs_trans_handle_cachep)
3307                 kmem_cache_destroy(btrfs_trans_handle_cachep);
3308         if (btrfs_transaction_cachep)
3309                 kmem_cache_destroy(btrfs_transaction_cachep);
3310         if (btrfs_bit_radix_cachep)
3311                 kmem_cache_destroy(btrfs_bit_radix_cachep);
3312         if (btrfs_path_cachep)
3313                 kmem_cache_destroy(btrfs_path_cachep);
3314 }
3315
3316 struct kmem_cache *btrfs_cache_create(const char *name, size_t size,
3317                                        unsigned long extra_flags,
3318 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3319                                        void (*ctor)(void *)
3320 #elif LINUX_VERSION_CODE > KERNEL_VERSION(2,6,23)
3321                                        void (*ctor)(struct kmem_cache *, void *)
3322 #else
3323                                        void (*ctor)(void *, struct kmem_cache *,
3324                                                     unsigned long)
3325 #endif
3326                                      )
3327 {
3328         return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
3329                                  SLAB_MEM_SPREAD | extra_flags), ctor
3330 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
3331                                  ,NULL
3332 #endif
3333                                 );
3334 }
3335
3336 int btrfs_init_cachep(void)
3337 {
3338         btrfs_inode_cachep = btrfs_cache_create("btrfs_inode_cache",
3339                                           sizeof(struct btrfs_inode),
3340                                           0, init_once);
3341         if (!btrfs_inode_cachep)
3342                 goto fail;
3343         btrfs_trans_handle_cachep =
3344                         btrfs_cache_create("btrfs_trans_handle_cache",
3345                                            sizeof(struct btrfs_trans_handle),
3346                                            0, NULL);
3347         if (!btrfs_trans_handle_cachep)
3348                 goto fail;
3349         btrfs_transaction_cachep = btrfs_cache_create("btrfs_transaction_cache",
3350                                              sizeof(struct btrfs_transaction),
3351                                              0, NULL);
3352         if (!btrfs_transaction_cachep)
3353                 goto fail;
3354         btrfs_path_cachep = btrfs_cache_create("btrfs_path_cache",
3355                                          sizeof(struct btrfs_path),
3356                                          0, NULL);
3357         if (!btrfs_path_cachep)
3358                 goto fail;
3359         btrfs_bit_radix_cachep = btrfs_cache_create("btrfs_radix", 256,
3360                                               SLAB_DESTROY_BY_RCU, NULL);
3361         if (!btrfs_bit_radix_cachep)
3362                 goto fail;
3363         return 0;
3364 fail:
3365         btrfs_destroy_cachep();
3366         return -ENOMEM;
3367 }
3368
3369 static int btrfs_getattr(struct vfsmount *mnt,
3370                          struct dentry *dentry, struct kstat *stat)
3371 {
3372         struct inode *inode = dentry->d_inode;
3373         generic_fillattr(inode, stat);
3374         stat->blksize = PAGE_CACHE_SIZE;
3375         stat->blocks = inode->i_blocks + (BTRFS_I(inode)->delalloc_bytes >> 9);
3376         return 0;
3377 }
3378
3379 static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
3380                            struct inode * new_dir,struct dentry *new_dentry)
3381 {
3382         struct btrfs_trans_handle *trans;
3383         struct btrfs_root *root = BTRFS_I(old_dir)->root;
3384         struct inode *new_inode = new_dentry->d_inode;
3385         struct inode *old_inode = old_dentry->d_inode;
3386         struct timespec ctime = CURRENT_TIME;
3387         int ret;
3388
3389         if (S_ISDIR(old_inode->i_mode) && new_inode &&
3390             new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
3391                 return -ENOTEMPTY;
3392         }
3393
3394         ret = btrfs_check_free_space(root, 1, 0);
3395         if (ret)
3396                 goto out_unlock;
3397
3398         trans = btrfs_start_transaction(root, 1);
3399
3400         btrfs_set_trans_block_group(trans, new_dir);
3401
3402         old_dentry->d_inode->i_nlink++;
3403         old_dir->i_ctime = old_dir->i_mtime = ctime;
3404         new_dir->i_ctime = new_dir->i_mtime = ctime;
3405         old_inode->i_ctime = ctime;
3406
3407         ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
3408         if (ret)
3409                 goto out_fail;
3410
3411         if (new_inode) {
3412                 new_inode->i_ctime = CURRENT_TIME;
3413                 ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
3414                 if (ret)
3415                         goto out_fail;
3416                 if (new_inode->i_nlink == 0) {
3417                         ret = btrfs_orphan_add(trans, new_inode);
3418                         if (ret)
3419                                 goto out_fail;
3420                 }
3421         }
3422         ret = btrfs_set_inode_index(new_dir, old_inode);
3423         if (ret)
3424                 goto out_fail;
3425
3426         ret = btrfs_add_link(trans, new_dentry, old_inode, 1);
3427         if (ret)
3428                 goto out_fail;
3429
3430 out_fail:
3431         btrfs_end_transaction_throttle(trans, root);
3432 out_unlock:
3433         return ret;
3434 }
3435
3436 int btrfs_start_delalloc_inodes(struct btrfs_root *root)
3437 {
3438         struct list_head *head = &root->fs_info->delalloc_inodes;
3439         struct btrfs_inode *binode;
3440         unsigned long flags;
3441
3442         spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
3443         while(!list_empty(head)) {
3444                 binode = list_entry(head->next, struct btrfs_inode,
3445                                     delalloc_inodes);
3446                 atomic_inc(&binode->vfs_inode.i_count);
3447                 spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
3448                 filemap_write_and_wait(binode->vfs_inode.i_mapping);
3449                 iput(&binode->vfs_inode);
3450                 spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
3451         }
3452         spin_unlock_irqrestore(&root->fs_info->delalloc_lock, flags);
3453         return 0;
3454 }
3455
3456 static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
3457                          const char *symname)
3458 {
3459         struct btrfs_trans_handle *trans;
3460         struct btrfs_root *root = BTRFS_I(dir)->root;
3461         struct btrfs_path *path;
3462         struct btrfs_key key;
3463         struct inode *inode = NULL;
3464         int err;
3465         int drop_inode = 0;
3466         u64 objectid;
3467         int name_len;
3468         int datasize;
3469         unsigned long ptr;
3470         struct btrfs_file_extent_item *ei;
3471         struct extent_buffer *leaf;
3472         unsigned long nr = 0;
3473
3474         name_len = strlen(symname) + 1;
3475         if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
3476                 return -ENAMETOOLONG;
3477
3478         err = btrfs_check_free_space(root, 1, 0);
3479         if (err)
3480                 goto out_fail;
3481
3482         trans = btrfs_start_transaction(root, 1);
3483         btrfs_set_trans_block_group(trans, dir);
3484
3485         err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
3486         if (err) {
3487                 err = -ENOSPC;
3488                 goto out_unlock;
3489         }
3490
3491         inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
3492                                 dentry->d_name.len,
3493                                 dentry->d_parent->d_inode->i_ino, objectid,
3494                                 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
3495         err = PTR_ERR(inode);
3496         if (IS_ERR(inode))
3497                 goto out_unlock;
3498
3499         err = btrfs_init_acl(inode, dir);
3500         if (err) {
3501                 drop_inode = 1;
3502                 goto out_unlock;
3503         }
3504
3505         btrfs_set_trans_block_group(trans, inode);
3506         err = btrfs_add_nondir(trans, dentry, inode, 0);
3507         if (err)
3508                 drop_inode = 1;
3509         else {
3510                 inode->i_mapping->a_ops = &btrfs_aops;
3511                 inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3512                 inode->i_fop = &btrfs_file_operations;
3513                 inode->i_op = &btrfs_file_inode_operations;
3514                 extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
3515                 extent_io_tree_init(&BTRFS_I(inode)->io_tree,
3516                                      inode->i_mapping, GFP_NOFS);
3517                 extent_io_tree_init(&BTRFS_I(inode)->io_failure_tree,
3518                                      inode->i_mapping, GFP_NOFS);
3519                 INIT_LIST_HEAD(&BTRFS_I(inode)->delalloc_inodes);
3520                 mutex_init(&BTRFS_I(inode)->csum_mutex);
3521                 mutex_init(&BTRFS_I(inode)->extent_mutex);
3522                 BTRFS_I(inode)->delalloc_bytes = 0;
3523                 BTRFS_I(inode)->disk_i_size = 0;
3524                 BTRFS_I(inode)->io_tree.ops = &btrfs_extent_io_ops;
3525                 btrfs_ordered_inode_tree_init(&BTRFS_I(inode)->ordered_tree);
3526         }
3527         dir->i_sb->s_dirt = 1;
3528         btrfs_update_inode_block_group(trans, inode);
3529         btrfs_update_inode_block_group(trans, dir);
3530         if (drop_inode)
3531                 goto out_unlock;
3532
3533         path = btrfs_alloc_path();
3534         BUG_ON(!path);
3535         key.objectid = inode->i_ino;
3536         key.offset = 0;
3537         btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
3538         datasize = btrfs_file_extent_calc_inline_size(name_len);
3539         err = btrfs_insert_empty_item(trans, root, path, &key,
3540                                       datasize);
3541         if (err) {
3542                 drop_inode = 1;
3543                 goto out_unlock;
3544         }
3545         leaf = path->nodes[0];
3546         ei = btrfs_item_ptr(leaf, path->slots[0],
3547                             struct btrfs_file_extent_item);
3548         btrfs_set_file_extent_generation(leaf, ei, trans->transid);
3549         btrfs_set_file_extent_type(leaf, ei,
3550                                    BTRFS_FILE_EXTENT_INLINE);
3551         ptr = btrfs_file_extent_inline_start(ei);
3552         write_extent_buffer(leaf, symname, ptr, name_len);
3553         btrfs_mark_buffer_dirty(leaf);
3554         btrfs_free_path(path);
3555
3556         inode->i_op = &btrfs_symlink_inode_operations;
3557         inode->i_mapping->a_ops = &btrfs_symlink_aops;
3558         inode->i_mapping->backing_dev_info = &root->fs_info->bdi;
3559         btrfs_i_size_write(inode, name_len - 1);
3560         err = btrfs_update_inode(trans, root, inode);
3561         if (err)
3562                 drop_inode = 1;
3563
3564 out_unlock:
3565         nr = trans->blocks_used;
3566         btrfs_end_transaction_throttle(trans, root);
3567 out_fail:
3568         if (drop_inode) {
3569                 inode_dec_link_count(inode);
3570                 iput(inode);
3571         }
3572         btrfs_btree_balance_dirty(root, nr);
3573         return err;
3574 }
3575
3576 static int btrfs_set_page_dirty(struct page *page)
3577 {
3578         return __set_page_dirty_nobuffers(page);
3579 }
3580
3581 #if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,26)
3582 static int btrfs_permission(struct inode *inode, int mask)
3583 #else
3584 static int btrfs_permission(struct inode *inode, int mask,
3585                             struct nameidata *nd)
3586 #endif
3587 {
3588         if (btrfs_test_flag(inode, READONLY) && (mask & MAY_WRITE))
3589                 return -EACCES;
3590         return generic_permission(inode, mask, btrfs_check_acl);
3591 }
3592
3593 static struct inode_operations btrfs_dir_inode_operations = {
3594         .lookup         = btrfs_lookup,
3595         .create         = btrfs_create,
3596         .unlink         = btrfs_unlink,
3597         .link           = btrfs_link,
3598         .mkdir          = btrfs_mkdir,
3599         .rmdir          = btrfs_rmdir,
3600         .rename         = btrfs_rename,
3601         .symlink        = btrfs_symlink,
3602         .setattr        = btrfs_setattr,
3603         .mknod          = btrfs_mknod,
3604         .setxattr       = generic_setxattr,
3605         .getxattr       = generic_getxattr,
3606         .listxattr      = btrfs_listxattr,
3607         .removexattr    = generic_removexattr,
3608         .permission     = btrfs_permission,
3609 };
3610 static struct inode_operations btrfs_dir_ro_inode_operations = {
3611         .lookup         = btrfs_lookup,
3612         .permission     = btrfs_permission,
3613 };
3614 static struct file_operations btrfs_dir_file_operations = {
3615         .llseek         = generic_file_llseek,
3616         .read           = generic_read_dir,
3617         .readdir        = btrfs_readdir,
3618         .unlocked_ioctl = btrfs_ioctl,
3619 #ifdef CONFIG_COMPAT
3620         .compat_ioctl   = btrfs_ioctl,
3621 #endif
3622         .release        = btrfs_release_file,
3623 };
3624
3625 static struct extent_io_ops btrfs_extent_io_ops = {
3626         .fill_delalloc = run_delalloc_range,
3627         .submit_bio_hook = btrfs_submit_bio_hook,
3628         .merge_bio_hook = btrfs_merge_bio_hook,
3629         .readpage_io_hook = btrfs_readpage_io_hook,
3630         .readpage_end_io_hook = btrfs_readpage_end_io_hook,
3631         .writepage_end_io_hook = btrfs_writepage_end_io_hook,
3632         .writepage_start_hook = btrfs_writepage_start_hook,
3633         .readpage_io_failed_hook = btrfs_io_failed_hook,
3634         .set_bit_hook = btrfs_set_bit_hook,
3635         .clear_bit_hook = btrfs_clear_bit_hook,
3636 };
3637
3638 static struct address_space_operations btrfs_aops = {
3639         .readpage       = btrfs_readpage,
3640         .writepage      = btrfs_writepage,
3641         .writepages     = btrfs_writepages,
3642         .readpages      = btrfs_readpages,
3643         .sync_page      = block_sync_page,
3644         .bmap           = btrfs_bmap,
3645         .direct_IO      = btrfs_direct_IO,
3646         .invalidatepage = btrfs_invalidatepage,
3647         .releasepage    = btrfs_releasepage,
3648         .set_page_dirty = btrfs_set_page_dirty,
3649 };
3650
3651 static struct address_space_operations btrfs_symlink_aops = {
3652         .readpage       = btrfs_readpage,
3653         .writepage      = btrfs_writepage,
3654         .invalidatepage = btrfs_invalidatepage,
3655         .releasepage    = btrfs_releasepage,
3656 };
3657
3658 static struct inode_operations btrfs_file_inode_operations = {
3659         .truncate       = btrfs_truncate,
3660         .getattr        = btrfs_getattr,
3661         .setattr        = btrfs_setattr,
3662         .setxattr       = generic_setxattr,
3663         .getxattr       = generic_getxattr,
3664         .listxattr      = btrfs_listxattr,
3665         .removexattr    = generic_removexattr,
3666         .permission     = btrfs_permission,
3667 };
3668 static struct inode_operations btrfs_special_inode_operations = {
3669         .getattr        = btrfs_getattr,
3670         .setattr        = btrfs_setattr,
3671         .permission     = btrfs_permission,
3672         .setxattr       = generic_setxattr,
3673         .getxattr       = generic_getxattr,
3674         .listxattr      = btrfs_listxattr,
3675         .removexattr    = generic_removexattr,
3676 };
3677 static struct inode_operations btrfs_symlink_inode_operations = {
3678         .readlink       = generic_readlink,
3679         .follow_link    = page_follow_link_light,
3680         .put_link       = page_put_link,
3681         .permission     = btrfs_permission,
3682 };