fs/btrfs/disk-io.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/fs.h>
  20 #include <linux/blkdev.h>
  21 #include <linux/crc32c.h>
  22 #include <linux/scatterlist.h>
  23 #include <linux/swap.h>
  24 #include <linux/radix-tree.h>
  25 #include <linux/writeback.h>
  26 #include <linux/buffer_head.h> // for block_sync_page
  27 #include "ctree.h"
  28 #include "disk-io.h"
  29 #include "transaction.h"
  30 #include "btrfs_inode.h"
  31
  32 #if 0
  33 static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
  34 {
  35         if (extent_buffer_blocknr(buf) != btrfs_header_blocknr(buf)) {
  36                 printk(KERN_CRIT "buf blocknr(buf) is %llu, header is %llu\n",
  37                        (unsigned long long)extent_buffer_blocknr(buf),
  38                        (unsigned long long)btrfs_header_blocknr(buf));
  39                 return 1;
  40         }
  41         return 0;
  42 }
  43 #endif
  44
  45 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
  46                                             u64 blocknr)
  47 {
  48         struct inode *btree_inode = root->fs_info->btree_inode;
  49         struct extent_buffer *eb;
  50         eb = find_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
  51                                    blocknr * root->sectorsize,
  52                                    root->sectorsize, GFP_NOFS);
  53         if (eb)
  54                 eb->alloc_addr = (unsigned long)__builtin_return_address(0);
  55         return eb;
  56 }
  57
  58 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
  59                                                  u64 blocknr)
  60 {
  61         struct inode *btree_inode = root->fs_info->btree_inode;
  62         struct extent_buffer *eb;
  63         eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
  64                                    blocknr * root->sectorsize,
  65                                    root->sectorsize, GFP_NOFS);
  66         eb->alloc_addr = (unsigned long)__builtin_return_address(0);
  67         return eb;
  68 }
  69
  70 struct extent_map *btree_get_extent(struct inode *inode, struct page *page,
  71                                     size_t page_offset, u64 start, u64 end,
  72                                     int create)
  73 {
  74         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
  75         struct extent_map *em;
  76         int ret;
  77
  78 again:
  79         em = lookup_extent_mapping(em_tree, start, end);
  80         if (em) {
  81                 goto out;
  82         }
  83         em = alloc_extent_map(GFP_NOFS);
  84         if (!em) {
  85                 em = ERR_PTR(-ENOMEM);
  86                 goto out;
  87         }
  88         em->start = 0;
  89         em->end = (i_size_read(inode) & ~((u64)PAGE_CACHE_SIZE -1)) - 1;
  90         em->block_start = 0;
  91         em->block_end = em->end;
  92         em->bdev = inode->i_sb->s_bdev;
  93         ret = add_extent_mapping(em_tree, em);
  94         if (ret == -EEXIST) {
  95                 free_extent_map(em);
  96                 em = NULL;
  97                 goto again;
  98         } else if (ret) {
  99                 em = ERR_PTR(ret);
 100         }
 101 out:
 102         return em;
 103 }
 104
 105 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 106 {
 107         struct extent_map_tree *tree;
 108         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 109         return extent_write_full_page(tree, page, btree_get_extent, wbc);
 110 }
 111 int btree_readpage(struct file *file, struct page *page)
 112 {
 113         struct extent_map_tree *tree;
 114         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 115         return extent_read_full_page(tree, page, btree_get_extent);
 116 }
 117
 118 static int btree_releasepage(struct page *page, gfp_t unused_gfp_flags)
 119 {
 120         struct extent_map_tree *tree;
 121         int ret;
 122
 123         BUG_ON(page->private != 1);
 124         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 125         ret = try_release_extent_mapping(tree, page);
 126         if (ret == 1) {
 127                 ClearPagePrivate(page);
 128                 set_page_private(page, 0);
 129                 page_cache_release(page);
 130         }
 131         return ret;
 132 }
 133
 134 static void btree_invalidatepage(struct page *page, unsigned long offset)
 135 {
 136         struct extent_map_tree *tree;
 137         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 138         extent_invalidatepage(tree, page, offset);
 139         btree_releasepage(page, GFP_NOFS);
 140 }
 141
 142 int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len,
 143                     char *result)
 144 {
 145         return 0;
 146 #if 0
 147         u32 crc;
 148         crc = crc32c(0, data, len);
 149         memcpy(result, &crc, BTRFS_CRC32_SIZE);
 150         return 0;
 151 #endif
 152 }
 153
 154 #if 0
 155 static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 156                            int verify)
 157 {
 158         return 0;
 159         char result[BTRFS_CRC32_SIZE];
 160         int ret;
 161         struct btrfs_node *node;
 162
 163         ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE,
 164                               bh->b_size - BTRFS_CSUM_SIZE, result);
 165         if (ret)
 166                 return ret;
 167         if (verify) {
 168                 if (memcmp(bh->b_data, result, BTRFS_CRC32_SIZE)) {
 169                         printk("btrfs: %s checksum verify failed on %llu\n",
 170                                root->fs_info->sb->s_id,
 171                                (unsigned long long)bh_blocknr(bh));
 172                         return 1;
 173                 }
 174         } else {
 175                 node = btrfs_buffer_node(bh);
 176                 memcpy(node->header.csum, result, BTRFS_CRC32_SIZE);
 177         }
 178         return 0;
 179 }
 180 #endif
 181
 182 #if 0
 183 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 184 {
 185         struct buffer_head *bh;
 186         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 187         struct buffer_head *head;
 188         if (!page_has_buffers(page)) {
 189                 create_empty_buffers(page, root->fs_info->sb->s_blocksize,
 190                                         (1 << BH_Dirty)|(1 << BH_Uptodate));
 191         }
 192         head = page_buffers(page);
 193         bh = head;
 194         do {
 195                 if (buffer_dirty(bh))
 196                         csum_tree_block(root, bh, 0);
 197                 bh = bh->b_this_page;
 198         } while (bh != head);
 199         return block_write_full_page(page, btree_get_block, wbc);
 200 }
 201 #endif
 202
 203 static struct address_space_operations btree_aops = {
 204         .readpage       = btree_readpage,
 205         .writepage      = btree_writepage,
 206         .releasepage    = btree_releasepage,
 207         .invalidatepage = btree_invalidatepage,
 208         .sync_page      = block_sync_page,
 209 };
 210
 211 int readahead_tree_block(struct btrfs_root *root, u64 blocknr)
 212 {
 213         struct extent_buffer *buf = NULL;
 214         struct inode *btree_inode = root->fs_info->btree_inode;
 215         int ret = 0;
 216
 217         buf = btrfs_find_create_tree_block(root, blocknr);
 218         if (!buf)
 219                 return 0;
 220         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 221                                  buf, 0);
 222         free_extent_buffer(buf);
 223         return ret;
 224 }
 225
 226 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr)
 227 {
 228         struct extent_buffer *buf = NULL;
 229         struct inode *btree_inode = root->fs_info->btree_inode;
 230
 231         buf = btrfs_find_create_tree_block(root, blocknr);
 232         if (!buf)
 233                 return NULL;
 234         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 235                                  buf, 1);
 236         buf->alloc_addr = (unsigned long)__builtin_return_address(0);
 237         return buf;
 238 }
 239
 240 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 241                      struct extent_buffer *buf)
 242 {
 243         struct inode *btree_inode = root->fs_info->btree_inode;
 244         clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 245         return 0;
 246 }
 247
 248 int wait_on_tree_block_writeback(struct btrfs_root *root,
 249                                  struct extent_buffer *buf)
 250 {
 251         struct inode *btree_inode = root->fs_info->btree_inode;
 252         wait_on_extent_buffer_writeback(&BTRFS_I(btree_inode)->extent_tree,
 253                                         buf);
 254         return 0;
 255 }
 256
 257 int set_tree_block_dirty(struct btrfs_root *root, struct extent_buffer *buf)
 258 {
 259         struct inode *btree_inode = root->fs_info->btree_inode;
 260         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 261         return 0;
 262 }
 263
 264 static int __setup_root(int blocksize,
 265                         struct btrfs_root *root,
 266                         struct btrfs_fs_info *fs_info,
 267                         u64 objectid)
 268 {
 269         root->node = NULL;
 270         root->inode = NULL;
 271         root->commit_root = NULL;
 272         root->sectorsize = blocksize;
 273         root->nodesize = blocksize;
 274         root->leafsize = blocksize;
 275         root->ref_cows = 0;
 276         root->fs_info = fs_info;
 277         root->objectid = objectid;
 278         root->last_trans = 0;
 279         root->highest_inode = 0;
 280         root->last_inode_alloc = 0;
 281         root->name = NULL;
 282         memset(&root->root_key, 0, sizeof(root->root_key));
 283         memset(&root->root_item, 0, sizeof(root->root_item));
 284         memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
 285         memset(&root->root_kobj, 0, sizeof(root->root_kobj));
 286         init_completion(&root->kobj_unregister);
 287         init_rwsem(&root->snap_sem);
 288         root->defrag_running = 0;
 289         root->defrag_level = 0;
 290         root->root_key.objectid = objectid;
 291         return 0;
 292 }
 293
 294 static int find_and_setup_root(int blocksize,
 295                                struct btrfs_root *tree_root,
 296                                struct btrfs_fs_info *fs_info,
 297                                u64 objectid,
 298                                struct btrfs_root *root)
 299 {
 300         int ret;
 301
 302         __setup_root(blocksize, root, fs_info, objectid);
 303         ret = btrfs_find_last_root(tree_root, objectid,
 304                                    &root->root_item, &root->root_key);
 305         BUG_ON(ret);
 306
 307         root->node = read_tree_block(root,
 308                                      btrfs_root_blocknr(&root->root_item));
 309         BUG_ON(!root->node);
 310         return 0;
 311 }
 312
 313 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
 314                                                struct btrfs_key *location)
 315 {
 316         struct btrfs_root *root;
 317         struct btrfs_root *tree_root = fs_info->tree_root;
 318         struct btrfs_path *path;
 319         struct extent_buffer *l;
 320         u64 highest_inode;
 321         int ret = 0;
 322
 323         root = kzalloc(sizeof(*root), GFP_NOFS);
 324         if (!root)
 325                 return ERR_PTR(-ENOMEM);
 326         if (location->offset == (u64)-1) {
 327                 ret = find_and_setup_root(fs_info->sb->s_blocksize,
 328                                           fs_info->tree_root, fs_info,
 329                                           location->objectid, root);
 330                 if (ret) {
 331                         kfree(root);
 332                         return ERR_PTR(ret);
 333                 }
 334                 goto insert;
 335         }
 336
 337         __setup_root(fs_info->sb->s_blocksize, root, fs_info,
 338                      location->objectid);
 339
 340         path = btrfs_alloc_path();
 341         BUG_ON(!path);
 342         ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
 343         if (ret != 0) {
 344                 if (ret > 0)
 345                         ret = -ENOENT;
 346                 goto out;
 347         }
 348         l = path->nodes[0];
 349         read_extent_buffer(l, &root->root_item,
 350                btrfs_item_ptr_offset(l, path->slots[0]),
 351                sizeof(root->root_item));
 352         ret = 0;
 353 out:
 354         btrfs_release_path(root, path);
 355         btrfs_free_path(path);
 356         if (ret) {
 357                 kfree(root);
 358                 return ERR_PTR(ret);
 359         }
 360         root->node = read_tree_block(root,
 361                                      btrfs_root_blocknr(&root->root_item));
 362         BUG_ON(!root->node);
 363 insert:
 364         root->ref_cows = 1;
 365         ret = btrfs_find_highest_inode(root, &highest_inode);
 366         if (ret == 0) {
 367                 root->highest_inode = highest_inode;
 368                 root->last_inode_alloc = highest_inode;
 369         }
 370         return root;
 371 }
 372
 373 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 374                                       struct btrfs_key *location,
 375                                       const char *name, int namelen)
 376 {
 377         struct btrfs_root *root;
 378         int ret;
 379
 380         root = radix_tree_lookup(&fs_info->fs_roots_radix,
 381                                  (unsigned long)location->objectid);
 382         if (root)
 383                 return root;
 384
 385         root = btrfs_read_fs_root_no_radix(fs_info, location);
 386         if (IS_ERR(root))
 387                 return root;
 388         ret = radix_tree_insert(&fs_info->fs_roots_radix,
 389                                 (unsigned long)root->root_key.objectid,
 390                                 root);
 391         if (ret) {
 392                 free_extent_buffer(root->node);
 393                 kfree(root);
 394                 return ERR_PTR(ret);
 395         }
 396
 397         ret = btrfs_set_root_name(root, name, namelen);
 398         if (ret) {
 399                 free_extent_buffer(root->node);
 400                 kfree(root);
 401                 return ERR_PTR(ret);
 402         }
 403
 404         ret = btrfs_sysfs_add_root(root);
 405         if (ret) {
 406                 free_extent_buffer(root->node);
 407                 kfree(root->name);
 408                 kfree(root);
 409                 return ERR_PTR(ret);
 410         }
 411
 412         ret = btrfs_find_dead_roots(fs_info->tree_root,
 413                                     root->root_key.objectid, root);
 414         BUG_ON(ret);
 415
 416         return root;
 417 }
 418
 419 struct btrfs_root *open_ctree(struct super_block *sb)
 420 {
 421         struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
 422                                                  GFP_NOFS);
 423         struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
 424                                                GFP_NOFS);
 425         struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
 426                                                 GFP_NOFS);
 427         int ret;
 428         int err = -EIO;
 429         struct btrfs_super_block *disk_super;
 430
 431         if (!extent_root || !tree_root || !fs_info) {
 432                 err = -ENOMEM;
 433                 goto fail;
 434         }
 435         init_bit_radix(&fs_info->pinned_radix);
 436         init_bit_radix(&fs_info->pending_del_radix);
 437         init_bit_radix(&fs_info->extent_ins_radix);
 438         INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
 439         INIT_LIST_HEAD(&fs_info->trans_list);
 440         INIT_LIST_HEAD(&fs_info->dead_roots);
 441         memset(&fs_info->super_kobj, 0, sizeof(fs_info->super_kobj));
 442         init_completion(&fs_info->kobj_unregister);
 443         sb_set_blocksize(sb, 4096);
 444         fs_info->running_transaction = NULL;
 445         fs_info->last_trans_committed = 0;
 446         fs_info->tree_root = tree_root;
 447         fs_info->extent_root = extent_root;
 448         fs_info->sb = sb;
 449         fs_info->btree_inode = new_inode(sb);
 450         fs_info->btree_inode->i_ino = 1;
 451         fs_info->btree_inode->i_nlink = 1;
 452         fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
 453         fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
 454         extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree,
 455                              fs_info->btree_inode->i_mapping,
 456                              GFP_NOFS);
 457         extent_map_tree_init(&fs_info->free_space_cache,
 458                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 459         extent_map_tree_init(&fs_info->block_group_cache,
 460                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 461         fs_info->do_barriers = 1;
 462         fs_info->closing = 0;
 463
 464         INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
 465         BTRFS_I(fs_info->btree_inode)->root = tree_root;
 466         memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
 467                sizeof(struct btrfs_key));
 468         insert_inode_hash(fs_info->btree_inode);
 469         mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
 470
 471         mutex_init(&fs_info->trans_mutex);
 472         mutex_init(&fs_info->fs_mutex);
 473
 474         __setup_root(sb->s_blocksize, tree_root,
 475                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
 476
 477         fs_info->sb_buffer = read_tree_block(tree_root,
 478                                              BTRFS_SUPER_INFO_OFFSET /
 479                                              sb->s_blocksize);
 480
 481         if (!fs_info->sb_buffer)
 482                 goto fail_iput;
 483
 484         read_extent_buffer(fs_info->sb_buffer, &fs_info->super_copy, 0,
 485                            sizeof(fs_info->super_copy));
 486
 487         read_extent_buffer(fs_info->sb_buffer, fs_info->fsid,
 488                            (unsigned long)btrfs_super_fsid(fs_info->sb_buffer),
 489                            BTRFS_FSID_SIZE);
 490         disk_super = &fs_info->super_copy;
 491         if (!btrfs_super_root(disk_super))
 492                 goto fail_sb_buffer;
 493
 494         i_size_write(fs_info->btree_inode,
 495                      btrfs_super_total_blocks(disk_super) <<
 496                      fs_info->btree_inode->i_blkbits);
 497
 498
 499         if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
 500                     sizeof(disk_super->magic))) {
 501                 printk("btrfs: valid FS not found on %s\n", sb->s_id);
 502                 goto fail_sb_buffer;
 503         }
 504         tree_root->node = read_tree_block(tree_root,
 505                                           btrfs_super_root(disk_super));
 506         if (!tree_root->node)
 507                 goto fail_sb_buffer;
 508
 509         mutex_lock(&fs_info->fs_mutex);
 510         ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
 511                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
 512         if (ret) {
 513                 mutex_unlock(&fs_info->fs_mutex);
 514                 goto fail_tree_root;
 515         }
 516
 517         btrfs_read_block_groups(extent_root);
 518
 519         fs_info->generation = btrfs_super_generation(disk_super) + 1;
 520         mutex_unlock(&fs_info->fs_mutex);
 521         return tree_root;
 522
 523 fail_tree_root:
 524         free_extent_buffer(tree_root->node);
 525 fail_sb_buffer:
 526         free_extent_buffer(fs_info->sb_buffer);
 527 fail_iput:
 528         iput(fs_info->btree_inode);
 529 fail:
 530         kfree(extent_root);
 531         kfree(tree_root);
 532         kfree(fs_info);
 533         return ERR_PTR(err);
 534 }
 535
 536 int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
 537                       *root)
 538 {
 539         int ret;
 540         struct extent_buffer *super = root->fs_info->sb_buffer;
 541         struct inode *btree_inode = root->fs_info->btree_inode;
 542
 543         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, super);
 544         ret = sync_page_range_nolock(btree_inode, btree_inode->i_mapping,
 545                                      super->start, super->len);
 546         return ret;
 547 }
 548
 549 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 550 {
 551         radix_tree_delete(&fs_info->fs_roots_radix,
 552                           (unsigned long)root->root_key.objectid);
 553         btrfs_sysfs_del_root(root);
 554         if (root->inode)
 555                 iput(root->inode);
 556         if (root->node)
 557                 free_extent_buffer(root->node);
 558         if (root->commit_root)
 559                 free_extent_buffer(root->commit_root);
 560         if (root->name)
 561                 kfree(root->name);
 562         kfree(root);
 563         return 0;
 564 }
 565
 566 static int del_fs_roots(struct btrfs_fs_info *fs_info)
 567 {
 568         int ret;
 569         struct btrfs_root *gang[8];
 570         int i;
 571
 572         while(1) {
 573                 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
 574                                              (void **)gang, 0,
 575                                              ARRAY_SIZE(gang));
 576                 if (!ret)
 577                         break;
 578                 for (i = 0; i < ret; i++)
 579                         btrfs_free_fs_root(fs_info, gang[i]);
 580         }
 581         return 0;
 582 }
 583
 584 int close_ctree(struct btrfs_root *root)
 585 {
 586         int ret;
 587         struct btrfs_trans_handle *trans;
 588         struct btrfs_fs_info *fs_info = root->fs_info;
 589
 590         fs_info->closing = 1;
 591         btrfs_transaction_flush_work(root);
 592         mutex_lock(&fs_info->fs_mutex);
 593         btrfs_defrag_dirty_roots(root->fs_info);
 594         trans = btrfs_start_transaction(root, 1);
 595         ret = btrfs_commit_transaction(trans, root);
 596         /* run commit again to  drop the original snapshot */
 597         trans = btrfs_start_transaction(root, 1);
 598         btrfs_commit_transaction(trans, root);
 599         ret = btrfs_write_and_wait_transaction(NULL, root);
 600         BUG_ON(ret);
 601         write_ctree_super(NULL, root);
 602         mutex_unlock(&fs_info->fs_mutex);
 603
 604         if (fs_info->extent_root->node)
 605                 free_extent_buffer(fs_info->extent_root->node);
 606
 607         if (fs_info->tree_root->node)
 608                 free_extent_buffer(fs_info->tree_root->node);
 609
 610         free_extent_buffer(fs_info->sb_buffer);
 611         truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
 612         iput(fs_info->btree_inode);
 613
 614         btrfs_free_block_groups(root->fs_info);
 615         del_fs_roots(fs_info);
 616         kfree(fs_info->extent_root);
 617         kfree(fs_info->tree_root);
 618         return 0;
 619 }
 620
 621 int btrfs_buffer_uptodate(struct extent_buffer *buf)
 622 {
 623         struct inode *btree_inode = buf->first_page->mapping->host;
 624         return extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree, buf);
 625 }
 626
 627 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
 628 {
 629         struct inode *btree_inode = buf->first_page->mapping->host;
 630         return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree,
 631                                           buf);
 632 }
 633
 634 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 635 {
 636         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 637         u64 transid = btrfs_header_generation(buf);
 638         struct inode *btree_inode = root->fs_info->btree_inode;
 639
 640         if (transid != root->fs_info->generation) {
 641                 printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
 642                         (unsigned long long)extent_buffer_blocknr(buf),
 643                         transid, root->fs_info->generation);
 644                 WARN_ON(1);
 645         }
 646         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 647 }
 648
 649 void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
 650 {
 651         balance_dirty_pages_ratelimited_nr(
 652                         root->fs_info->btree_inode->i_mapping, nr);
 653 }