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, NULL, 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 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
 103 {
 104         return crc32c(seed, data, len);
 105 }
 106
 107 void btrfs_csum_final(u32 crc, char *result)
 108 {
 109         *(__le32 *)result = ~cpu_to_le32(crc);
 110 }
 111
 112 static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 113                            int verify)
 114 {
 115         char result[BTRFS_CRC32_SIZE];
 116         unsigned long len;
 117         unsigned long cur_len;
 118         unsigned long offset = BTRFS_CSUM_SIZE;
 119         char *map_token = NULL;
 120         char *kaddr;
 121         unsigned long map_start;
 122         unsigned long map_len;
 123         int err;
 124         u32 crc = ~(u32)0;
 125
 126         len = buf->len - offset;
 127         while(len > 0) {
 128                 err = map_private_extent_buffer(buf, offset, 32,
 129                                         &map_token, &kaddr,
 130                                         &map_start, &map_len, KM_USER0);
 131                 if (err) {
 132                         printk("failed to map extent buffer! %lu\n",
 133                                offset);
 134                         return 1;
 135                 }
 136                 cur_len = min(len, map_len - (offset - map_start));
 137                 crc = btrfs_csum_data(root, kaddr + offset - map_start,
 138                                       crc, cur_len);
 139                 len -= cur_len;
 140                 offset += cur_len;
 141                 unmap_extent_buffer(buf, map_token, KM_USER0);
 142         }
 143         btrfs_csum_final(crc, result);
 144
 145         if (verify) {
 146                 if (memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) {
 147                         printk("btrfs: %s checksum verify failed on %llu\n",
 148                                root->fs_info->sb->s_id,
 149                                buf->start);
 150                         return 1;
 151                 }
 152         } else {
 153                 write_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE);
 154         }
 155         return 0;
 156 }
 157
 158
 159 int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 160 {
 161         struct extent_map_tree *tree;
 162         u64 start = page->index << PAGE_CACHE_SHIFT;
 163         u64 found_start;
 164         int found_level;
 165         unsigned long len;
 166         struct extent_buffer *eb;
 167         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 168
 169         if (page->private == EXTENT_PAGE_PRIVATE)
 170                 goto out;
 171         if (!page->private)
 172                 goto out;
 173         len = page->private >> 2;
 174         if (len == 0) {
 175                 WARN_ON(1);
 176         }
 177         eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS);
 178         read_extent_buffer_pages(tree, eb, start + PAGE_CACHE_SIZE, 1);
 179         found_start = btrfs_header_bytenr(eb);
 180         if (found_start != start) {
 181                 printk("warning: eb start incorrect %Lu buffer %Lu len %lu\n",
 182                        start, found_start, len);
 183         }
 184         found_level = btrfs_header_level(eb);
 185         csum_tree_block(root, eb, 0);
 186         free_extent_buffer(eb);
 187 out:
 188         return 0;
 189 }
 190
 191 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 192 {
 193         struct extent_map_tree *tree;
 194         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 195         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 196
 197         csum_dirty_buffer(root, page);
 198         return extent_write_full_page(tree, page, btree_get_extent, wbc);
 199 }
 200 int btree_readpage(struct file *file, struct page *page)
 201 {
 202         struct extent_map_tree *tree;
 203         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 204         return extent_read_full_page(tree, page, btree_get_extent);
 205 }
 206
 207 static int btree_releasepage(struct page *page, gfp_t unused_gfp_flags)
 208 {
 209         struct extent_map_tree *tree;
 210         int ret;
 211
 212         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 213         ret = try_release_extent_mapping(tree, page);
 214         if (ret == 1) {
 215                 ClearPagePrivate(page);
 216                 set_page_private(page, 0);
 217                 page_cache_release(page);
 218         }
 219         return ret;
 220 }
 221
 222 static void btree_invalidatepage(struct page *page, unsigned long offset)
 223 {
 224         struct extent_map_tree *tree;
 225         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 226         extent_invalidatepage(tree, page, offset);
 227         btree_releasepage(page, GFP_NOFS);
 228 }
 229
 230 #if 0
 231 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 232 {
 233         struct buffer_head *bh;
 234         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 235         struct buffer_head *head;
 236         if (!page_has_buffers(page)) {
 237                 create_empty_buffers(page, root->fs_info->sb->s_blocksize,
 238                                         (1 << BH_Dirty)|(1 << BH_Uptodate));
 239         }
 240         head = page_buffers(page);
 241         bh = head;
 242         do {
 243                 if (buffer_dirty(bh))
 244                         csum_tree_block(root, bh, 0);
 245                 bh = bh->b_this_page;
 246         } while (bh != head);
 247         return block_write_full_page(page, btree_get_block, wbc);
 248 }
 249 #endif
 250
 251 static struct address_space_operations btree_aops = {
 252         .readpage       = btree_readpage,
 253         .writepage      = btree_writepage,
 254         .releasepage    = btree_releasepage,
 255         .invalidatepage = btree_invalidatepage,
 256         .sync_page      = block_sync_page,
 257 };
 258
 259 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize)
 260 {
 261         struct extent_buffer *buf = NULL;
 262         struct inode *btree_inode = root->fs_info->btree_inode;
 263         int ret = 0;
 264
 265         buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 266         if (!buf)
 267                 return 0;
 268         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 269                                  buf, 0, 0);
 270         free_extent_buffer(buf);
 271         return ret;
 272 }
 273
 274 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 275                                       u32 blocksize)
 276 {
 277         struct extent_buffer *buf = NULL;
 278         struct inode *btree_inode = root->fs_info->btree_inode;
 279         struct extent_map_tree *extent_tree;
 280         int ret;
 281
 282         extent_tree = &BTRFS_I(btree_inode)->extent_tree;
 283
 284         buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 285         if (!buf)
 286                 return NULL;
 287         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 288                                  buf, 0, 1);
 289         if (buf->flags & EXTENT_CSUM) {
 290                 return buf;
 291         }
 292         if (test_range_bit(extent_tree, buf->start, buf->start + buf->len - 1,
 293                            EXTENT_CSUM, 1)) {
 294                 buf->flags |= EXTENT_CSUM;
 295                 return buf;
 296         }
 297         ret = csum_tree_block(root, buf, 1);
 298         set_extent_bits(extent_tree, buf->start,
 299                         buf->start + buf->len - 1,
 300                         EXTENT_CSUM, GFP_NOFS);
 301         buf->flags |= EXTENT_CSUM;
 302         return buf;
 303 }
 304
 305 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 306                      struct extent_buffer *buf)
 307 {
 308         struct inode *btree_inode = root->fs_info->btree_inode;
 309         clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 310         return 0;
 311 }
 312
 313 int wait_on_tree_block_writeback(struct btrfs_root *root,
 314                                  struct extent_buffer *buf)
 315 {
 316         struct inode *btree_inode = root->fs_info->btree_inode;
 317         wait_on_extent_buffer_writeback(&BTRFS_I(btree_inode)->extent_tree,
 318                                         buf);
 319         return 0;
 320 }
 321
 322 static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 323                         struct btrfs_root *root,
 324                         struct btrfs_fs_info *fs_info,
 325                         u64 objectid)
 326 {
 327         root->node = NULL;
 328         root->inode = NULL;
 329         root->commit_root = NULL;
 330         root->sectorsize = sectorsize;
 331         root->nodesize = nodesize;
 332         root->leafsize = leafsize;
 333         root->ref_cows = 0;
 334         root->fs_info = fs_info;
 335         root->objectid = objectid;
 336         root->last_trans = 0;
 337         root->highest_inode = 0;
 338         root->last_inode_alloc = 0;
 339         root->name = NULL;
 340         memset(&root->root_key, 0, sizeof(root->root_key));
 341         memset(&root->root_item, 0, sizeof(root->root_item));
 342         memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
 343         memset(&root->root_kobj, 0, sizeof(root->root_kobj));
 344         init_completion(&root->kobj_unregister);
 345         init_rwsem(&root->snap_sem);
 346         root->defrag_running = 0;
 347         root->defrag_level = 0;
 348         root->root_key.objectid = objectid;
 349         return 0;
 350 }
 351
 352 static int find_and_setup_root(struct btrfs_root *tree_root,
 353                                struct btrfs_fs_info *fs_info,
 354                                u64 objectid,
 355                                struct btrfs_root *root)
 356 {
 357         int ret;
 358         u32 blocksize;
 359
 360         __setup_root(tree_root->nodesize, tree_root->leafsize,
 361                      tree_root->sectorsize, root, fs_info, objectid);
 362         ret = btrfs_find_last_root(tree_root, objectid,
 363                                    &root->root_item, &root->root_key);
 364         BUG_ON(ret);
 365
 366         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 367         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 368                                      blocksize);
 369         BUG_ON(!root->node);
 370         return 0;
 371 }
 372
 373 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
 374                                                struct btrfs_key *location)
 375 {
 376         struct btrfs_root *root;
 377         struct btrfs_root *tree_root = fs_info->tree_root;
 378         struct btrfs_path *path;
 379         struct extent_buffer *l;
 380         u64 highest_inode;
 381         u32 blocksize;
 382         int ret = 0;
 383
 384         root = kzalloc(sizeof(*root), GFP_NOFS);
 385         if (!root)
 386                 return ERR_PTR(-ENOMEM);
 387         if (location->offset == (u64)-1) {
 388                 ret = find_and_setup_root(tree_root, fs_info,
 389                                           location->objectid, root);
 390                 if (ret) {
 391                         kfree(root);
 392                         return ERR_PTR(ret);
 393                 }
 394                 goto insert;
 395         }
 396
 397         __setup_root(tree_root->nodesize, tree_root->leafsize,
 398                      tree_root->sectorsize, root, fs_info,
 399                      location->objectid);
 400
 401         path = btrfs_alloc_path();
 402         BUG_ON(!path);
 403         ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
 404         if (ret != 0) {
 405                 if (ret > 0)
 406                         ret = -ENOENT;
 407                 goto out;
 408         }
 409         l = path->nodes[0];
 410         read_extent_buffer(l, &root->root_item,
 411                btrfs_item_ptr_offset(l, path->slots[0]),
 412                sizeof(root->root_item));
 413         ret = 0;
 414 out:
 415         btrfs_release_path(root, path);
 416         btrfs_free_path(path);
 417         if (ret) {
 418                 kfree(root);
 419                 return ERR_PTR(ret);
 420         }
 421         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 422         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 423                                      blocksize);
 424         BUG_ON(!root->node);
 425 insert:
 426         root->ref_cows = 1;
 427         ret = btrfs_find_highest_inode(root, &highest_inode);
 428         if (ret == 0) {
 429                 root->highest_inode = highest_inode;
 430                 root->last_inode_alloc = highest_inode;
 431         }
 432         return root;
 433 }
 434
 435 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 436                                       struct btrfs_key *location,
 437                                       const char *name, int namelen)
 438 {
 439         struct btrfs_root *root;
 440         int ret;
 441
 442         root = radix_tree_lookup(&fs_info->fs_roots_radix,
 443                                  (unsigned long)location->objectid);
 444         if (root)
 445                 return root;
 446
 447         root = btrfs_read_fs_root_no_radix(fs_info, location);
 448         if (IS_ERR(root))
 449                 return root;
 450         ret = radix_tree_insert(&fs_info->fs_roots_radix,
 451                                 (unsigned long)root->root_key.objectid,
 452                                 root);
 453         if (ret) {
 454                 free_extent_buffer(root->node);
 455                 kfree(root);
 456                 return ERR_PTR(ret);
 457         }
 458
 459         ret = btrfs_set_root_name(root, name, namelen);
 460         if (ret) {
 461                 free_extent_buffer(root->node);
 462                 kfree(root);
 463                 return ERR_PTR(ret);
 464         }
 465
 466         ret = btrfs_sysfs_add_root(root);
 467         if (ret) {
 468                 free_extent_buffer(root->node);
 469                 kfree(root->name);
 470                 kfree(root);
 471                 return ERR_PTR(ret);
 472         }
 473
 474         ret = btrfs_find_dead_roots(fs_info->tree_root,
 475                                     root->root_key.objectid, root);
 476         BUG_ON(ret);
 477
 478         return root;
 479 }
 480 #if 0
 481 static int add_hasher(struct btrfs_fs_info *info, char *type) {
 482         struct btrfs_hasher *hasher;
 483
 484         hasher = kmalloc(sizeof(*hasher), GFP_NOFS);
 485         if (!hasher)
 486                 return -ENOMEM;
 487         hasher->hash_tfm = crypto_alloc_hash(type, 0, CRYPTO_ALG_ASYNC);
 488         if (!hasher->hash_tfm) {
 489                 kfree(hasher);
 490                 return -EINVAL;
 491         }
 492         spin_lock(&info->hash_lock);
 493         list_add(&hasher->list, &info->hashers);
 494         spin_unlock(&info->hash_lock);
 495         return 0;
 496 }
 497 #endif
 498 struct btrfs_root *open_ctree(struct super_block *sb)
 499 {
 500         u32 sectorsize;
 501         u32 nodesize;
 502         u32 leafsize;
 503         u32 blocksize;
 504         struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
 505                                                  GFP_NOFS);
 506         struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
 507                                                GFP_NOFS);
 508         struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
 509                                                 GFP_NOFS);
 510         int ret;
 511         int err = -EIO;
 512         struct btrfs_super_block *disk_super;
 513
 514         if (!extent_root || !tree_root || !fs_info) {
 515                 err = -ENOMEM;
 516                 goto fail;
 517         }
 518         INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
 519         INIT_LIST_HEAD(&fs_info->trans_list);
 520         INIT_LIST_HEAD(&fs_info->dead_roots);
 521         INIT_LIST_HEAD(&fs_info->hashers);
 522         spin_lock_init(&fs_info->hash_lock);
 523
 524         memset(&fs_info->super_kobj, 0, sizeof(fs_info->super_kobj));
 525         init_completion(&fs_info->kobj_unregister);
 526         sb_set_blocksize(sb, 4096);
 527         fs_info->running_transaction = NULL;
 528         fs_info->last_trans_committed = 0;
 529         fs_info->tree_root = tree_root;
 530         fs_info->extent_root = extent_root;
 531         fs_info->sb = sb;
 532         fs_info->btree_inode = new_inode(sb);
 533         fs_info->btree_inode->i_ino = 1;
 534         fs_info->btree_inode->i_nlink = 1;
 535         fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
 536         fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
 537         extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree,
 538                              fs_info->btree_inode->i_mapping,
 539                              GFP_NOFS);
 540         extent_map_tree_init(&fs_info->free_space_cache,
 541                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 542         extent_map_tree_init(&fs_info->block_group_cache,
 543                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 544         extent_map_tree_init(&fs_info->pinned_extents,
 545                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 546         extent_map_tree_init(&fs_info->pending_del,
 547                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 548         extent_map_tree_init(&fs_info->extent_ins,
 549                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 550         fs_info->do_barriers = 1;
 551         fs_info->closing = 0;
 552
 553         INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
 554         BTRFS_I(fs_info->btree_inode)->root = tree_root;
 555         memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
 556                sizeof(struct btrfs_key));
 557         insert_inode_hash(fs_info->btree_inode);
 558         mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
 559
 560         mutex_init(&fs_info->trans_mutex);
 561         mutex_init(&fs_info->fs_mutex);
 562
 563 #if 0
 564         ret = add_hasher(fs_info, "crc32c");
 565         if (ret) {
 566                 printk("btrfs: failed hash setup, modprobe cryptomgr?\n");
 567                 err = -ENOMEM;
 568                 goto fail_iput;
 569         }
 570 #endif
 571         __setup_root(512, 512, 512, tree_root,
 572                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
 573
 574         fs_info->sb_buffer = read_tree_block(tree_root,
 575                                              BTRFS_SUPER_INFO_OFFSET,
 576                                              512);
 577
 578         if (!fs_info->sb_buffer)
 579                 goto fail_iput;
 580
 581         read_extent_buffer(fs_info->sb_buffer, &fs_info->super_copy, 0,
 582                            sizeof(fs_info->super_copy));
 583
 584         read_extent_buffer(fs_info->sb_buffer, fs_info->fsid,
 585                            (unsigned long)btrfs_super_fsid(fs_info->sb_buffer),
 586                            BTRFS_FSID_SIZE);
 587         disk_super = &fs_info->super_copy;
 588         if (!btrfs_super_root(disk_super))
 589                 goto fail_sb_buffer;
 590
 591         nodesize = btrfs_super_nodesize(disk_super);
 592         leafsize = btrfs_super_leafsize(disk_super);
 593         sectorsize = btrfs_super_sectorsize(disk_super);
 594         tree_root->nodesize = nodesize;
 595         tree_root->leafsize = leafsize;
 596         tree_root->sectorsize = sectorsize;
 597         sb_set_blocksize(sb, sectorsize);
 598
 599         i_size_write(fs_info->btree_inode,
 600                      btrfs_super_total_bytes(disk_super));
 601
 602         if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
 603                     sizeof(disk_super->magic))) {
 604                 printk("btrfs: valid FS not found on %s\n", sb->s_id);
 605                 goto fail_sb_buffer;
 606         }
 607
 608         blocksize = btrfs_level_size(tree_root,
 609                                      btrfs_super_root_level(disk_super));
 610
 611         tree_root->node = read_tree_block(tree_root,
 612                                           btrfs_super_root(disk_super),
 613                                           blocksize);
 614         if (!tree_root->node)
 615                 goto fail_sb_buffer;
 616
 617         mutex_lock(&fs_info->fs_mutex);
 618
 619         ret = find_and_setup_root(tree_root, fs_info,
 620                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
 621         if (ret) {
 622                 mutex_unlock(&fs_info->fs_mutex);
 623                 goto fail_tree_root;
 624         }
 625
 626         btrfs_read_block_groups(extent_root);
 627
 628         fs_info->generation = btrfs_super_generation(disk_super) + 1;
 629         mutex_unlock(&fs_info->fs_mutex);
 630         return tree_root;
 631
 632 fail_tree_root:
 633         free_extent_buffer(tree_root->node);
 634 fail_sb_buffer:
 635         free_extent_buffer(fs_info->sb_buffer);
 636 fail_iput:
 637         iput(fs_info->btree_inode);
 638 fail:
 639         kfree(extent_root);
 640         kfree(tree_root);
 641         kfree(fs_info);
 642         return ERR_PTR(err);
 643 }
 644
 645 int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
 646                       *root)
 647 {
 648         int ret;
 649         struct extent_buffer *super = root->fs_info->sb_buffer;
 650         struct inode *btree_inode = root->fs_info->btree_inode;
 651
 652         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, super);
 653         ret = sync_page_range_nolock(btree_inode, btree_inode->i_mapping,
 654                                      super->start, super->len);
 655         return ret;
 656 }
 657
 658 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 659 {
 660         radix_tree_delete(&fs_info->fs_roots_radix,
 661                           (unsigned long)root->root_key.objectid);
 662         btrfs_sysfs_del_root(root);
 663         if (root->inode)
 664                 iput(root->inode);
 665         if (root->node)
 666                 free_extent_buffer(root->node);
 667         if (root->commit_root)
 668                 free_extent_buffer(root->commit_root);
 669         if (root->name)
 670                 kfree(root->name);
 671         kfree(root);
 672         return 0;
 673 }
 674
 675 static int del_fs_roots(struct btrfs_fs_info *fs_info)
 676 {
 677         int ret;
 678         struct btrfs_root *gang[8];
 679         int i;
 680
 681         while(1) {
 682                 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
 683                                              (void **)gang, 0,
 684                                              ARRAY_SIZE(gang));
 685                 if (!ret)
 686                         break;
 687                 for (i = 0; i < ret; i++)
 688                         btrfs_free_fs_root(fs_info, gang[i]);
 689         }
 690         return 0;
 691 }
 692
 693 int close_ctree(struct btrfs_root *root)
 694 {
 695         int ret;
 696         struct btrfs_trans_handle *trans;
 697         struct btrfs_fs_info *fs_info = root->fs_info;
 698
 699         fs_info->closing = 1;
 700         btrfs_transaction_flush_work(root);
 701         mutex_lock(&fs_info->fs_mutex);
 702         btrfs_defrag_dirty_roots(root->fs_info);
 703         trans = btrfs_start_transaction(root, 1);
 704         ret = btrfs_commit_transaction(trans, root);
 705         /* run commit again to  drop the original snapshot */
 706         trans = btrfs_start_transaction(root, 1);
 707         btrfs_commit_transaction(trans, root);
 708         ret = btrfs_write_and_wait_transaction(NULL, root);
 709         BUG_ON(ret);
 710         write_ctree_super(NULL, root);
 711         mutex_unlock(&fs_info->fs_mutex);
 712
 713         if (fs_info->extent_root->node)
 714                 free_extent_buffer(fs_info->extent_root->node);
 715
 716         if (fs_info->tree_root->node)
 717                 free_extent_buffer(fs_info->tree_root->node);
 718
 719         free_extent_buffer(fs_info->sb_buffer);
 720
 721         btrfs_free_block_groups(root->fs_info);
 722         del_fs_roots(fs_info);
 723         extent_map_tree_empty_lru(&BTRFS_I(fs_info->btree_inode)->extent_tree);
 724         truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
 725         iput(fs_info->btree_inode);
 726 #if 0
 727         while(!list_empty(&fs_info->hashers)) {
 728                 struct btrfs_hasher *hasher;
 729                 hasher = list_entry(fs_info->hashers.next, struct btrfs_hasher,
 730                                     hashers);
 731                 list_del(&hasher->hashers);
 732                 crypto_free_hash(&fs_info->hash_tfm);
 733                 kfree(hasher);
 734         }
 735 #endif
 736         kfree(fs_info->extent_root);
 737         kfree(fs_info->tree_root);
 738         return 0;
 739 }
 740
 741 int btrfs_buffer_uptodate(struct extent_buffer *buf)
 742 {
 743         struct inode *btree_inode = buf->first_page->mapping->host;
 744         return extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree, buf);
 745 }
 746
 747 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
 748 {
 749         struct inode *btree_inode = buf->first_page->mapping->host;
 750         return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree,
 751                                           buf);
 752 }
 753
 754 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 755 {
 756         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 757         u64 transid = btrfs_header_generation(buf);
 758         struct inode *btree_inode = root->fs_info->btree_inode;
 759
 760         if (transid != root->fs_info->generation) {
 761                 printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
 762                         (unsigned long long)buf->start,
 763                         transid, root->fs_info->generation);
 764                 WARN_ON(1);
 765         }
 766         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 767 }
 768
 769 void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
 770 {
 771         balance_dirty_pages_ratelimited_nr(
 772                         root->fs_info->btree_inode->i_mapping, 1);
 773 }
 774
 775 void btrfs_set_buffer_defrag(struct extent_buffer *buf)
 776 {
 777         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 778         struct inode *btree_inode = root->fs_info->btree_inode;
 779         set_extent_bits(&BTRFS_I(btree_inode)->extent_tree, buf->start,
 780                         buf->start + buf->len - 1, EXTENT_DEFRAG, GFP_NOFS);
 781 }
 782
 783 void btrfs_set_buffer_defrag_done(struct extent_buffer *buf)
 784 {
 785         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 786         struct inode *btree_inode = root->fs_info->btree_inode;
 787         set_extent_bits(&BTRFS_I(btree_inode)->extent_tree, buf->start,
 788                         buf->start + buf->len - 1, EXTENT_DEFRAG_DONE,
 789                         GFP_NOFS);
 790 }
 791
 792 int btrfs_buffer_defrag(struct extent_buffer *buf)
 793 {
 794         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 795         struct inode *btree_inode = root->fs_info->btree_inode;
 796         return test_range_bit(&BTRFS_I(btree_inode)->extent_tree,
 797                      buf->start, buf->start + buf->len - 1, EXTENT_DEFRAG, 0);
 798 }
 799
 800 int btrfs_buffer_defrag_done(struct extent_buffer *buf)
 801 {
 802         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 803         struct inode *btree_inode = root->fs_info->btree_inode;
 804         return test_range_bit(&BTRFS_I(btree_inode)->extent_tree,
 805                      buf->start, buf->start + buf->len - 1,
 806                      EXTENT_DEFRAG_DONE, 0);
 807 }
 808
 809 int btrfs_clear_buffer_defrag_done(struct extent_buffer *buf)
 810 {
 811         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 812         struct inode *btree_inode = root->fs_info->btree_inode;
 813         return clear_extent_bits(&BTRFS_I(btree_inode)->extent_tree,
 814                      buf->start, buf->start + buf->len - 1,
 815                      EXTENT_DEFRAG_DONE, GFP_NOFS);
 816 }
 817
 818 int btrfs_clear_buffer_defrag(struct extent_buffer *buf)
 819 {
 820         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 821         struct inode *btree_inode = root->fs_info->btree_inode;
 822         return clear_extent_bits(&BTRFS_I(btree_inode)->extent_tree,
 823                      buf->start, buf->start + buf->len - 1,
 824                      EXTENT_DEFRAG, GFP_NOFS);
 825 }
 826
 827 int btrfs_read_buffer(struct extent_buffer *buf)
 828 {
 829         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 830         struct inode *btree_inode = root->fs_info->btree_inode;
 831         return read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 832                                         buf, 0, 1);
 833 }