git.oblomov.eu Git - linux-2.6/blob - 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 #include "print-tree.h"
  32
  33 #if 0
  34 static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
  35 {
  36         if (extent_buffer_blocknr(buf) != btrfs_header_blocknr(buf)) {
  37                 printk(KERN_CRIT "buf blocknr(buf) is %llu, header is %llu\n",
  38                        (unsigned long long)extent_buffer_blocknr(buf),
  39                        (unsigned long long)btrfs_header_blocknr(buf));
  40                 return 1;
  41         }
  42         return 0;
  43 }
  44 #endif
  45
  46 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
  47                                             u64 bytenr, u32 blocksize)
  48 {
  49         struct inode *btree_inode = root->fs_info->btree_inode;
  50         struct extent_buffer *eb;
  51         eb = find_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
  52                                 bytenr, blocksize, GFP_NOFS);
  53         return eb;
  54 }
  55
  56 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
  57                                                  u64 bytenr, u32 blocksize)
  58 {
  59         struct inode *btree_inode = root->fs_info->btree_inode;
  60         struct extent_buffer *eb;
  61
  62         eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
  63                                  bytenr, blocksize, GFP_NOFS);
  64         return eb;
  65 }
  66
  67 struct extent_map *btree_get_extent(struct inode *inode, struct page *page,
  68                                     size_t page_offset, u64 start, u64 end,
  69                                     int create)
  70 {
  71         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
  72         struct extent_map *em;
  73         int ret;
  74
  75 again:
  76         em = lookup_extent_mapping(em_tree, start, end);
  77         if (em) {
  78                 goto out;
  79         }
  80         em = alloc_extent_map(GFP_NOFS);
  81         if (!em) {
  82                 em = ERR_PTR(-ENOMEM);
  83                 goto out;
  84         }
  85         em->start = 0;
  86         em->end = (i_size_read(inode) & ~((u64)PAGE_CACHE_SIZE -1)) - 1;
  87         em->block_start = 0;
  88         em->block_end = em->end;
  89         em->bdev = inode->i_sb->s_bdev;
  90         ret = add_extent_mapping(em_tree, em);
  91         if (ret == -EEXIST) {
  92                 free_extent_map(em);
  93                 em = NULL;
  94                 goto again;
  95         } else if (ret) {
  96                 em = ERR_PTR(ret);
  97         }
  98 out:
  99         return em;
 100 }
 101
 102 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 103 {
 104         struct extent_map_tree *tree;
 105         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 106         return extent_write_full_page(tree, page, btree_get_extent, wbc);
 107 }
 108 int btree_readpage(struct file *file, struct page *page)
 109 {
 110         struct extent_map_tree *tree;
 111         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 112         return extent_read_full_page(tree, page, btree_get_extent);
 113 }
 114
 115 static int btree_releasepage(struct page *page, gfp_t unused_gfp_flags)
 116 {
 117         struct extent_map_tree *tree;
 118         int ret;
 119
 120         BUG_ON(page->private != 1);
 121         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 122         ret = try_release_extent_mapping(tree, page);
 123         if (ret == 1) {
 124                 ClearPagePrivate(page);
 125                 set_page_private(page, 0);
 126                 page_cache_release(page);
 127         }
 128         return ret;
 129 }
 130
 131 static void btree_invalidatepage(struct page *page, unsigned long offset)
 132 {
 133         struct extent_map_tree *tree;
 134         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 135         extent_invalidatepage(tree, page, offset);
 136         btree_releasepage(page, GFP_NOFS);
 137 }
 138
 139 int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len,
 140                     char *result)
 141 {
 142         return 0;
 143 #if 0
 144         u32 crc;
 145         crc = crc32c(0, data, len);
 146         memcpy(result, &crc, BTRFS_CRC32_SIZE);
 147         return 0;
 148 #endif
 149 }
 150
 151 #if 0
 152 static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 153                            int verify)
 154 {
 155         return 0;
 156         char result[BTRFS_CRC32_SIZE];
 157         int ret;
 158         struct btrfs_node *node;
 159
 160         ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE,
 161                               bh->b_size - BTRFS_CSUM_SIZE, result);
 162         if (ret)
 163                 return ret;
 164         if (verify) {
 165                 if (memcmp(bh->b_data, result, BTRFS_CRC32_SIZE)) {
 166                         printk("btrfs: %s checksum verify failed on %llu\n",
 167                                root->fs_info->sb->s_id,
 168                                (unsigned long long)bh_blocknr(bh));
 169                         return 1;
 170                 }
 171         } else {
 172                 node = btrfs_buffer_node(bh);
 173                 memcpy(node->header.csum, result, BTRFS_CRC32_SIZE);
 174         }
 175         return 0;
 176 }
 177 #endif
 178
 179 #if 0
 180 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 181 {
 182         struct buffer_head *bh;
 183         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 184         struct buffer_head *head;
 185         if (!page_has_buffers(page)) {
 186                 create_empty_buffers(page, root->fs_info->sb->s_blocksize,
 187                                         (1 << BH_Dirty)|(1 << BH_Uptodate));
 188         }
 189         head = page_buffers(page);
 190         bh = head;
 191         do {
 192                 if (buffer_dirty(bh))
 193                         csum_tree_block(root, bh, 0);
 194                 bh = bh->b_this_page;
 195         } while (bh != head);
 196         return block_write_full_page(page, btree_get_block, wbc);
 197 }
 198 #endif
 199
 200 static struct address_space_operations btree_aops = {
 201         .readpage       = btree_readpage,
 202         .writepage      = btree_writepage,
 203         .releasepage    = btree_releasepage,
 204         .invalidatepage = btree_invalidatepage,
 205         .sync_page      = block_sync_page,
 206 };
 207
 208 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize)
 209 {
 210         struct extent_buffer *buf = NULL;
 211         struct inode *btree_inode = root->fs_info->btree_inode;
 212         int ret = 0;
 213
 214         buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 215         if (!buf)
 216                 return 0;
 217         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 218                                  buf, 0);
 219         free_extent_buffer(buf);
 220         return ret;
 221 }
 222
 223 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 224                                       u32 blocksize)
 225 {
 226         struct extent_buffer *buf = NULL;
 227         struct inode *btree_inode = root->fs_info->btree_inode;
 228
 229         buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 230         if (!buf)
 231                 return NULL;
 232         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 233                                  buf, 1);
 234         return buf;
 235 }
 236
 237 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 238                      struct extent_buffer *buf)
 239 {
 240         struct inode *btree_inode = root->fs_info->btree_inode;
 241         clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 242         return 0;
 243 }
 244
 245 int wait_on_tree_block_writeback(struct btrfs_root *root,
 246                                  struct extent_buffer *buf)
 247 {
 248         struct inode *btree_inode = root->fs_info->btree_inode;
 249         wait_on_extent_buffer_writeback(&BTRFS_I(btree_inode)->extent_tree,
 250                                         buf);
 251         return 0;
 252 }
 253
 254 int set_tree_block_dirty(struct btrfs_root *root, struct extent_buffer *buf)
 255 {
 256         struct inode *btree_inode = root->fs_info->btree_inode;
 257         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 258         return 0;
 259 }
 260
 261 static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 262                         struct btrfs_root *root,
 263                         struct btrfs_fs_info *fs_info,
 264                         u64 objectid)
 265 {
 266         root->node = NULL;
 267         root->inode = NULL;
 268         root->commit_root = NULL;
 269         root->sectorsize = sectorsize;
 270         root->nodesize = nodesize;
 271         root->leafsize = leafsize;
 272         root->ref_cows = 0;
 273         root->fs_info = fs_info;
 274         root->objectid = objectid;
 275         root->last_trans = 0;
 276         root->highest_inode = 0;
 277         root->last_inode_alloc = 0;
 278         root->name = NULL;
 279         memset(&root->root_key, 0, sizeof(root->root_key));
 280         memset(&root->root_item, 0, sizeof(root->root_item));
 281         memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
 282         memset(&root->root_kobj, 0, sizeof(root->root_kobj));
 283         init_completion(&root->kobj_unregister);
 284         init_rwsem(&root->snap_sem);
 285         root->defrag_running = 0;
 286         root->defrag_level = 0;
 287         root->root_key.objectid = objectid;
 288         return 0;
 289 }
 290
 291 static int find_and_setup_root(struct btrfs_root *tree_root,
 292                                struct btrfs_fs_info *fs_info,
 293                                u64 objectid,
 294                                struct btrfs_root *root)
 295 {
 296         int ret;
 297         u32 blocksize;
 298
 299         __setup_root(tree_root->nodesize, tree_root->leafsize,
 300                      tree_root->sectorsize, root, fs_info, objectid);
 301         ret = btrfs_find_last_root(tree_root, objectid,
 302                                    &root->root_item, &root->root_key);
 303         BUG_ON(ret);
 304
 305         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 306         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 307                                      blocksize);
 308         BUG_ON(!root->node);
 309         return 0;
 310 }
 311
 312 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
 313                                                struct btrfs_key *location)
 314 {
 315         struct btrfs_root *root;
 316         struct btrfs_root *tree_root = fs_info->tree_root;
 317         struct btrfs_path *path;
 318         struct extent_buffer *l;
 319         u64 highest_inode;
 320         u32 blocksize;
 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(tree_root, fs_info,
 328                                           location->objectid, root);
 329                 if (ret) {
 330                         kfree(root);
 331                         return ERR_PTR(ret);
 332                 }
 333                 goto insert;
 334         }
 335
 336         __setup_root(tree_root->nodesize, tree_root->leafsize,
 337                      tree_root->sectorsize, 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         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 361         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 362                                      blocksize);
 363         BUG_ON(!root->node);
 364 insert:
 365         root->ref_cows = 1;
 366         ret = btrfs_find_highest_inode(root, &highest_inode);
 367         if (ret == 0) {
 368                 root->highest_inode = highest_inode;
 369                 root->last_inode_alloc = highest_inode;
 370         }
 371         return root;
 372 }
 373
 374 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 375                                       struct btrfs_key *location,
 376                                       const char *name, int namelen)
 377 {
 378         struct btrfs_root *root;
 379         int ret;
 380
 381         root = radix_tree_lookup(&fs_info->fs_roots_radix,
 382                                  (unsigned long)location->objectid);
 383         if (root)
 384                 return root;
 385
 386         root = btrfs_read_fs_root_no_radix(fs_info, location);
 387         if (IS_ERR(root))
 388                 return root;
 389         ret = radix_tree_insert(&fs_info->fs_roots_radix,
 390                                 (unsigned long)root->root_key.objectid,
 391                                 root);
 392         if (ret) {
 393                 free_extent_buffer(root->node);
 394                 kfree(root);
 395                 return ERR_PTR(ret);
 396         }
 397
 398         ret = btrfs_set_root_name(root, name, namelen);
 399         if (ret) {
 400                 free_extent_buffer(root->node);
 401                 kfree(root);
 402                 return ERR_PTR(ret);
 403         }
 404
 405         ret = btrfs_sysfs_add_root(root);
 406         if (ret) {
 407                 free_extent_buffer(root->node);
 408                 kfree(root->name);
 409                 kfree(root);
 410                 return ERR_PTR(ret);
 411         }
 412
 413         ret = btrfs_find_dead_roots(fs_info->tree_root,
 414                                     root->root_key.objectid, root);
 415         BUG_ON(ret);
 416
 417         return root;
 418 }
 419
 420 struct btrfs_root *open_ctree(struct super_block *sb)
 421 {
 422         u32 sectorsize;
 423         u32 nodesize;
 424         u32 leafsize;
 425         u32 blocksize;
 426         struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
 427                                                  GFP_NOFS);
 428         struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
 429                                                GFP_NOFS);
 430         struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
 431                                                 GFP_NOFS);
 432         int ret;
 433         int err = -EIO;
 434         struct btrfs_super_block *disk_super;
 435
 436         if (!extent_root || !tree_root || !fs_info) {
 437                 err = -ENOMEM;
 438                 goto fail;
 439         }
 440         INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
 441         INIT_LIST_HEAD(&fs_info->trans_list);
 442         INIT_LIST_HEAD(&fs_info->dead_roots);
 443         memset(&fs_info->super_kobj, 0, sizeof(fs_info->super_kobj));
 444         init_completion(&fs_info->kobj_unregister);
 445         sb_set_blocksize(sb, 4096);
 446         fs_info->running_transaction = NULL;
 447         fs_info->last_trans_committed = 0;
 448         fs_info->tree_root = tree_root;
 449         fs_info->extent_root = extent_root;
 450         fs_info->sb = sb;
 451         fs_info->btree_inode = new_inode(sb);
 452         fs_info->btree_inode->i_ino = 1;
 453         fs_info->btree_inode->i_nlink = 1;
 454         fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
 455         fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
 456         extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree,
 457                              fs_info->btree_inode->i_mapping,
 458                              GFP_NOFS);
 459         extent_map_tree_init(&fs_info->free_space_cache,
 460                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 461         extent_map_tree_init(&fs_info->block_group_cache,
 462                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 463         extent_map_tree_init(&fs_info->pinned_extents,
 464                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 465         extent_map_tree_init(&fs_info->pending_del,
 466                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 467         extent_map_tree_init(&fs_info->extent_ins,
 468                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 469         fs_info->do_barriers = 1;
 470         fs_info->closing = 0;
 471
 472         INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
 473         BTRFS_I(fs_info->btree_inode)->root = tree_root;
 474         memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
 475                sizeof(struct btrfs_key));
 476         insert_inode_hash(fs_info->btree_inode);
 477         mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
 478
 479         mutex_init(&fs_info->trans_mutex);
 480         mutex_init(&fs_info->fs_mutex);
 481
 482         __setup_root(512, 512, 512, tree_root,
 483                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
 484
 485         fs_info->sb_buffer = read_tree_block(tree_root,
 486                                              BTRFS_SUPER_INFO_OFFSET,
 487                                              512);
 488
 489         if (!fs_info->sb_buffer)
 490                 goto fail_iput;
 491
 492         read_extent_buffer(fs_info->sb_buffer, &fs_info->super_copy, 0,
 493                            sizeof(fs_info->super_copy));
 494
 495         read_extent_buffer(fs_info->sb_buffer, fs_info->fsid,
 496                            (unsigned long)btrfs_super_fsid(fs_info->sb_buffer),
 497                            BTRFS_FSID_SIZE);
 498         disk_super = &fs_info->super_copy;
 499         if (!btrfs_super_root(disk_super))
 500                 goto fail_sb_buffer;
 501
 502         nodesize = btrfs_super_nodesize(disk_super);
 503         leafsize = btrfs_super_leafsize(disk_super);
 504         sectorsize = btrfs_super_sectorsize(disk_super);
 505         tree_root->nodesize = nodesize;
 506         tree_root->leafsize = leafsize;
 507         tree_root->sectorsize = sectorsize;
 508
 509         i_size_write(fs_info->btree_inode,
 510                      btrfs_super_total_bytes(disk_super));
 511
 512
 513         if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
 514                     sizeof(disk_super->magic))) {
 515                 printk("btrfs: valid FS not found on %s\n", sb->s_id);
 516                 goto fail_sb_buffer;
 517         }
 518         blocksize = btrfs_level_size(tree_root,
 519                                      btrfs_super_root_level(disk_super));
 520         tree_root->node = read_tree_block(tree_root,
 521                                           btrfs_super_root(disk_super),
 522                                           blocksize);
 523         if (!tree_root->node)
 524                 goto fail_sb_buffer;
 525
 526 #if 0
 527         btrfs_print_leaf(tree_root, tree_root->node);
 528         err = -EIO;
 529         goto fail_tree_root;
 530 #endif
 531         mutex_lock(&fs_info->fs_mutex);
 532
 533         ret = find_and_setup_root(tree_root, fs_info,
 534                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
 535         if (ret) {
 536                 mutex_unlock(&fs_info->fs_mutex);
 537                 goto fail_tree_root;
 538         }
 539
 540         btrfs_read_block_groups(extent_root);
 541
 542         fs_info->generation = btrfs_super_generation(disk_super) + 1;
 543         mutex_unlock(&fs_info->fs_mutex);
 544         return tree_root;
 545
 546 fail_tree_root:
 547         free_extent_buffer(tree_root->node);
 548 fail_sb_buffer:
 549         free_extent_buffer(fs_info->sb_buffer);
 550 fail_iput:
 551         iput(fs_info->btree_inode);
 552 fail:
 553         kfree(extent_root);
 554         kfree(tree_root);
 555         kfree(fs_info);
 556         return ERR_PTR(err);
 557 }
 558
 559 int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
 560                       *root)
 561 {
 562         int ret;
 563         struct extent_buffer *super = root->fs_info->sb_buffer;
 564         struct inode *btree_inode = root->fs_info->btree_inode;
 565
 566         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, super);
 567         ret = sync_page_range_nolock(btree_inode, btree_inode->i_mapping,
 568                                      super->start, super->len);
 569         return ret;
 570 }
 571
 572 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 573 {
 574         radix_tree_delete(&fs_info->fs_roots_radix,
 575                           (unsigned long)root->root_key.objectid);
 576         btrfs_sysfs_del_root(root);
 577         if (root->inode)
 578                 iput(root->inode);
 579         if (root->node)
 580                 free_extent_buffer(root->node);
 581         if (root->commit_root)
 582                 free_extent_buffer(root->commit_root);
 583         if (root->name)
 584                 kfree(root->name);
 585         kfree(root);
 586         return 0;
 587 }
 588
 589 static int del_fs_roots(struct btrfs_fs_info *fs_info)
 590 {
 591         int ret;
 592         struct btrfs_root *gang[8];
 593         int i;
 594
 595         while(1) {
 596                 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
 597                                              (void **)gang, 0,
 598                                              ARRAY_SIZE(gang));
 599                 if (!ret)
 600                         break;
 601                 for (i = 0; i < ret; i++)
 602                         btrfs_free_fs_root(fs_info, gang[i]);
 603         }
 604         return 0;
 605 }
 606
 607 int close_ctree(struct btrfs_root *root)
 608 {
 609         int ret;
 610         struct btrfs_trans_handle *trans;
 611         struct btrfs_fs_info *fs_info = root->fs_info;
 612
 613         fs_info->closing = 1;
 614         btrfs_transaction_flush_work(root);
 615         mutex_lock(&fs_info->fs_mutex);
 616         btrfs_defrag_dirty_roots(root->fs_info);
 617         trans = btrfs_start_transaction(root, 1);
 618         ret = btrfs_commit_transaction(trans, root);
 619         /* run commit again to  drop the original snapshot */
 620         trans = btrfs_start_transaction(root, 1);
 621         btrfs_commit_transaction(trans, root);
 622         ret = btrfs_write_and_wait_transaction(NULL, root);
 623         BUG_ON(ret);
 624         write_ctree_super(NULL, root);
 625         mutex_unlock(&fs_info->fs_mutex);
 626
 627         if (fs_info->extent_root->node)
 628                 free_extent_buffer(fs_info->extent_root->node);
 629
 630         if (fs_info->tree_root->node)
 631                 free_extent_buffer(fs_info->tree_root->node);
 632
 633         free_extent_buffer(fs_info->sb_buffer);
 634
 635         btrfs_free_block_groups(root->fs_info);
 636         del_fs_roots(fs_info);
 637         extent_map_tree_cleanup(&BTRFS_I(fs_info->btree_inode)->extent_tree);
 638         truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
 639         iput(fs_info->btree_inode);
 640         kfree(fs_info->extent_root);
 641         kfree(fs_info->tree_root);
 642         return 0;
 643 }
 644
 645 int btrfs_buffer_uptodate(struct extent_buffer *buf)
 646 {
 647         struct inode *btree_inode = buf->last_page->mapping->host;
 648         return extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree, buf);
 649 }
 650
 651 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
 652 {
 653         struct inode *btree_inode = buf->last_page->mapping->host;
 654         return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree,
 655                                           buf);
 656 }
 657
 658 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 659 {
 660         struct btrfs_root *root = BTRFS_I(buf->last_page->mapping->host)->root;
 661         u64 transid = btrfs_header_generation(buf);
 662         struct inode *btree_inode = root->fs_info->btree_inode;
 663
 664         if (transid != root->fs_info->generation) {
 665                 printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
 666                         (unsigned long long)buf->start,
 667                         transid, root->fs_info->generation);
 668                 WARN_ON(1);
 669         }
 670         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 671 }
 672
 673 void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
 674 {
 675         balance_dirty_pages_ratelimited_nr(
 676                         root->fs_info->btree_inode->i_mapping, nr);
 677 }
 678
 679 void btrfs_set_buffer_defrag(struct extent_buffer *buf)
 680 {
 681         struct btrfs_root *root = BTRFS_I(buf->last_page->mapping->host)->root;
 682         struct inode *btree_inode = root->fs_info->btree_inode;
 683         set_extent_bits(&BTRFS_I(btree_inode)->extent_tree, buf->start,
 684                         buf->start + buf->len - 1, EXTENT_DEFRAG, GFP_NOFS);
 685 }
 686
 687 void btrfs_set_buffer_defrag_done(struct extent_buffer *buf)
 688 {
 689         struct btrfs_root *root = BTRFS_I(buf->last_page->mapping->host)->root;
 690         struct inode *btree_inode = root->fs_info->btree_inode;
 691         set_extent_bits(&BTRFS_I(btree_inode)->extent_tree, buf->start,
 692                         buf->start + buf->len - 1, EXTENT_DEFRAG_DONE,
 693                         GFP_NOFS);
 694 }
 695
 696 int btrfs_buffer_defrag(struct extent_buffer *buf)
 697 {
 698         struct btrfs_root *root = BTRFS_I(buf->last_page->mapping->host)->root;
 699         struct inode *btree_inode = root->fs_info->btree_inode;
 700         return test_range_bit(&BTRFS_I(btree_inode)->extent_tree,
 701                      buf->start, buf->start + buf->len - 1, EXTENT_DEFRAG, 0);
 702 }
 703
 704 int btrfs_buffer_defrag_done(struct extent_buffer *buf)
 705 {
 706         struct btrfs_root *root = BTRFS_I(buf->last_page->mapping->host)->root;
 707         struct inode *btree_inode = root->fs_info->btree_inode;
 708         return test_range_bit(&BTRFS_I(btree_inode)->extent_tree,
 709                      buf->start, buf->start + buf->len - 1,
 710                      EXTENT_DEFRAG_DONE, 0);
 711 }
 712
 713 int btrfs_clear_buffer_defrag_done(struct extent_buffer *buf)
 714 {
 715         struct btrfs_root *root = BTRFS_I(buf->last_page->mapping->host)->root;
 716         struct inode *btree_inode = root->fs_info->btree_inode;
 717         return clear_extent_bits(&BTRFS_I(btree_inode)->extent_tree,
 718                      buf->start, buf->start + buf->len - 1,
 719                      EXTENT_DEFRAG_DONE, GFP_NOFS);
 720 }
 721
 722 int btrfs_clear_buffer_defrag(struct extent_buffer *buf)
 723 {
 724         struct btrfs_root *root = BTRFS_I(buf->last_page->mapping->host)->root;
 725         struct inode *btree_inode = root->fs_info->btree_inode;
 726         return clear_extent_bits(&BTRFS_I(btree_inode)->extent_tree,
 727                      buf->start, buf->start + buf->len - 1,
 728                      EXTENT_DEFRAG, GFP_NOFS);
 729 }
 730
 731 int btrfs_read_buffer(struct extent_buffer *buf)
 732 {
 733         struct btrfs_root *root = BTRFS_I(buf->last_page->mapping->host)->root;
 734         struct inode *btree_inode = root->fs_info->btree_inode;
 735         return read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 736                                         buf, 1);
 737 }