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 static struct extent_map_ops btree_extent_map_ops;
  47
  48 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
  49                                             u64 bytenr, u32 blocksize)
  50 {
  51         struct inode *btree_inode = root->fs_info->btree_inode;
  52         struct extent_buffer *eb;
  53         eb = find_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
  54                                 bytenr, blocksize, GFP_NOFS);
  55         return eb;
  56 }
  57
  58 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
  59                                                  u64 bytenr, u32 blocksize)
  60 {
  61         struct inode *btree_inode = root->fs_info->btree_inode;
  62         struct extent_buffer *eb;
  63
  64         eb = alloc_extent_buffer(&BTRFS_I(btree_inode)->extent_tree,
  65                                  bytenr, blocksize, NULL, GFP_NOFS);
  66         return eb;
  67 }
  68
  69 struct extent_map *btree_get_extent(struct inode *inode, struct page *page,
  70                                     size_t page_offset, u64 start, u64 end,
  71                                     int create)
  72 {
  73         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
  74         struct extent_map *em;
  75         int ret;
  76
  77 again:
  78         em = lookup_extent_mapping(em_tree, start, end);
  79         if (em) {
  80                 goto out;
  81         }
  82         em = alloc_extent_map(GFP_NOFS);
  83         if (!em) {
  84                 em = ERR_PTR(-ENOMEM);
  85                 goto out;
  86         }
  87         em->start = 0;
  88         em->end = (i_size_read(inode) & ~((u64)PAGE_CACHE_SIZE -1)) - 1;
  89         em->block_start = 0;
  90         em->block_end = em->end;
  91         em->bdev = inode->i_sb->s_bdev;
  92         ret = add_extent_mapping(em_tree, em);
  93         if (ret == -EEXIST) {
  94                 free_extent_map(em);
  95                 em = NULL;
  96                 goto again;
  97         } else if (ret) {
  98                 em = ERR_PTR(ret);
  99         }
 100 out:
 101         return em;
 102 }
 103
 104 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)
 105 {
 106         return crc32c(seed, data, len);
 107 }
 108
 109 void btrfs_csum_final(u32 crc, char *result)
 110 {
 111         *(__le32 *)result = ~cpu_to_le32(crc);
 112 }
 113
 114 static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 115                            int verify)
 116 {
 117         char result[BTRFS_CRC32_SIZE];
 118         unsigned long len;
 119         unsigned long cur_len;
 120         unsigned long offset = BTRFS_CSUM_SIZE;
 121         char *map_token = NULL;
 122         char *kaddr;
 123         unsigned long map_start;
 124         unsigned long map_len;
 125         int err;
 126         u32 crc = ~(u32)0;
 127
 128         len = buf->len - offset;
 129         while(len > 0) {
 130                 err = map_private_extent_buffer(buf, offset, 32,
 131                                         &map_token, &kaddr,
 132                                         &map_start, &map_len, KM_USER0);
 133                 if (err) {
 134                         printk("failed to map extent buffer! %lu\n",
 135                                offset);
 136                         return 1;
 137                 }
 138                 cur_len = min(len, map_len - (offset - map_start));
 139                 crc = btrfs_csum_data(root, kaddr + offset - map_start,
 140                                       crc, cur_len);
 141                 len -= cur_len;
 142                 offset += cur_len;
 143                 unmap_extent_buffer(buf, map_token, KM_USER0);
 144         }
 145         btrfs_csum_final(crc, result);
 146
 147         if (verify) {
 148                 if (memcmp_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE)) {
 149                         printk("btrfs: %s checksum verify failed on %llu\n",
 150                                root->fs_info->sb->s_id,
 151                                buf->start);
 152                         return 1;
 153                 }
 154         } else {
 155                 write_extent_buffer(buf, result, 0, BTRFS_CRC32_SIZE);
 156         }
 157         return 0;
 158 }
 159
 160
 161 int csum_dirty_buffer(struct btrfs_root *root, struct page *page)
 162 {
 163         struct extent_map_tree *tree;
 164         u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
 165         u64 found_start;
 166         int found_level;
 167         unsigned long len;
 168         struct extent_buffer *eb;
 169         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 170
 171         if (page->private == EXTENT_PAGE_PRIVATE)
 172                 goto out;
 173         if (!page->private)
 174                 goto out;
 175         len = page->private >> 2;
 176         if (len == 0) {
 177                 WARN_ON(1);
 178         }
 179         eb = alloc_extent_buffer(tree, start, len, page, GFP_NOFS);
 180         read_extent_buffer_pages(tree, eb, start + PAGE_CACHE_SIZE, 1);
 181         found_start = btrfs_header_bytenr(eb);
 182         if (found_start != start) {
 183                 printk("warning: eb start incorrect %Lu buffer %Lu len %lu\n",
 184                        start, found_start, len);
 185         }
 186         found_level = btrfs_header_level(eb);
 187         csum_tree_block(root, eb, 0);
 188         free_extent_buffer(eb);
 189 out:
 190         return 0;
 191 }
 192
 193 static int btree_writepage_io_hook(struct page *page, u64 start, u64 end)
 194 {
 195         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 196
 197         csum_dirty_buffer(root, page);
 198         return 0;
 199 }
 200
 201 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 202 {
 203         struct extent_map_tree *tree;
 204         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 205         return extent_write_full_page(tree, page, btree_get_extent, wbc);
 206 }
 207
 208 static int btree_writepages(struct address_space *mapping,
 209                             struct writeback_control *wbc)
 210 {
 211         struct extent_map_tree *tree;
 212         tree = &BTRFS_I(mapping->host)->extent_tree;
 213         if (wbc->sync_mode == WB_SYNC_NONE) {
 214                 u64 num_dirty;
 215                 u64 start = 0;
 216                 unsigned long thresh = 96 * 1024 * 1024;
 217
 218                 if (wbc->for_kupdate)
 219                         return 0;
 220
 221                 if (current_is_pdflush()) {
 222                         thresh = 96 * 1024 * 1024;
 223                 } else {
 224                         thresh = 8 * 1024 * 1024;
 225                 }
 226                 num_dirty = count_range_bits(tree, &start, (u64)-1,
 227                                              thresh, EXTENT_DIRTY);
 228                 if (num_dirty < thresh) {
 229                         return 0;
 230                 }
 231         }
 232         return extent_writepages(tree, mapping, btree_get_extent, wbc);
 233 }
 234
 235 int btree_readpage(struct file *file, struct page *page)
 236 {
 237         struct extent_map_tree *tree;
 238         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 239         return extent_read_full_page(tree, page, btree_get_extent);
 240 }
 241
 242 static int btree_releasepage(struct page *page, gfp_t unused_gfp_flags)
 243 {
 244         struct extent_map_tree *tree;
 245         int ret;
 246
 247         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 248         ret = try_release_extent_mapping(tree, page);
 249         if (ret == 1) {
 250                 ClearPagePrivate(page);
 251                 set_page_private(page, 0);
 252                 page_cache_release(page);
 253         }
 254         return ret;
 255 }
 256
 257 static void btree_invalidatepage(struct page *page, unsigned long offset)
 258 {
 259         struct extent_map_tree *tree;
 260         tree = &BTRFS_I(page->mapping->host)->extent_tree;
 261         extent_invalidatepage(tree, page, offset);
 262         btree_releasepage(page, GFP_NOFS);
 263 }
 264
 265 #if 0
 266 static int btree_writepage(struct page *page, struct writeback_control *wbc)
 267 {
 268         struct buffer_head *bh;
 269         struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
 270         struct buffer_head *head;
 271         if (!page_has_buffers(page)) {
 272                 create_empty_buffers(page, root->fs_info->sb->s_blocksize,
 273                                         (1 << BH_Dirty)|(1 << BH_Uptodate));
 274         }
 275         head = page_buffers(page);
 276         bh = head;
 277         do {
 278                 if (buffer_dirty(bh))
 279                         csum_tree_block(root, bh, 0);
 280                 bh = bh->b_this_page;
 281         } while (bh != head);
 282         return block_write_full_page(page, btree_get_block, wbc);
 283 }
 284 #endif
 285
 286 static struct address_space_operations btree_aops = {
 287         .readpage       = btree_readpage,
 288         .writepage      = btree_writepage,
 289         .writepages     = btree_writepages,
 290         .releasepage    = btree_releasepage,
 291         .invalidatepage = btree_invalidatepage,
 292         .sync_page      = block_sync_page,
 293 };
 294
 295 int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize)
 296 {
 297         struct extent_buffer *buf = NULL;
 298         struct inode *btree_inode = root->fs_info->btree_inode;
 299         int ret = 0;
 300
 301         buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 302         if (!buf)
 303                 return 0;
 304         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 305                                  buf, 0, 0);
 306         free_extent_buffer(buf);
 307         return ret;
 308 }
 309
 310 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
 311                                       u32 blocksize)
 312 {
 313         struct extent_buffer *buf = NULL;
 314         struct inode *btree_inode = root->fs_info->btree_inode;
 315         struct extent_map_tree *extent_tree;
 316         int ret;
 317
 318         extent_tree = &BTRFS_I(btree_inode)->extent_tree;
 319
 320         buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
 321         if (!buf)
 322                 return NULL;
 323         read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 324                                  buf, 0, 1);
 325         if (buf->flags & EXTENT_CSUM) {
 326                 return buf;
 327         }
 328         if (test_range_bit(extent_tree, buf->start, buf->start + buf->len - 1,
 329                            EXTENT_CSUM, 1)) {
 330                 buf->flags |= EXTENT_CSUM;
 331                 return buf;
 332         }
 333         ret = csum_tree_block(root, buf, 1);
 334         set_extent_bits(extent_tree, buf->start,
 335                         buf->start + buf->len - 1,
 336                         EXTENT_CSUM, GFP_NOFS);
 337         buf->flags |= EXTENT_CSUM;
 338         return buf;
 339 }
 340
 341 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 342                      struct extent_buffer *buf)
 343 {
 344         struct inode *btree_inode = root->fs_info->btree_inode;
 345         clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 346         return 0;
 347 }
 348
 349 int wait_on_tree_block_writeback(struct btrfs_root *root,
 350                                  struct extent_buffer *buf)
 351 {
 352         struct inode *btree_inode = root->fs_info->btree_inode;
 353         wait_on_extent_buffer_writeback(&BTRFS_I(btree_inode)->extent_tree,
 354                                         buf);
 355         return 0;
 356 }
 357
 358 static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
 359                         u32 stripesize, struct btrfs_root *root,
 360                         struct btrfs_fs_info *fs_info,
 361                         u64 objectid)
 362 {
 363         root->node = NULL;
 364         root->inode = NULL;
 365         root->commit_root = NULL;
 366         root->sectorsize = sectorsize;
 367         root->nodesize = nodesize;
 368         root->leafsize = leafsize;
 369         root->stripesize = stripesize;
 370         root->ref_cows = 0;
 371         root->fs_info = fs_info;
 372         root->objectid = objectid;
 373         root->last_trans = 0;
 374         root->highest_inode = 0;
 375         root->last_inode_alloc = 0;
 376         root->name = NULL;
 377         root->in_sysfs = 0;
 378         memset(&root->root_key, 0, sizeof(root->root_key));
 379         memset(&root->root_item, 0, sizeof(root->root_item));
 380         memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
 381         memset(&root->root_kobj, 0, sizeof(root->root_kobj));
 382         init_completion(&root->kobj_unregister);
 383         init_rwsem(&root->snap_sem);
 384         root->defrag_running = 0;
 385         root->defrag_level = 0;
 386         root->root_key.objectid = objectid;
 387         return 0;
 388 }
 389
 390 static int find_and_setup_root(struct btrfs_root *tree_root,
 391                                struct btrfs_fs_info *fs_info,
 392                                u64 objectid,
 393                                struct btrfs_root *root)
 394 {
 395         int ret;
 396         u32 blocksize;
 397
 398         __setup_root(tree_root->nodesize, tree_root->leafsize,
 399                      tree_root->sectorsize, tree_root->stripesize,
 400                      root, fs_info, objectid);
 401         ret = btrfs_find_last_root(tree_root, objectid,
 402                                    &root->root_item, &root->root_key);
 403         BUG_ON(ret);
 404
 405         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 406         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 407                                      blocksize);
 408         BUG_ON(!root->node);
 409         return 0;
 410 }
 411
 412 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
 413                                                struct btrfs_key *location)
 414 {
 415         struct btrfs_root *root;
 416         struct btrfs_root *tree_root = fs_info->tree_root;
 417         struct btrfs_path *path;
 418         struct extent_buffer *l;
 419         u64 highest_inode;
 420         u32 blocksize;
 421         int ret = 0;
 422
 423         root = kzalloc(sizeof(*root), GFP_NOFS);
 424         if (!root)
 425                 return ERR_PTR(-ENOMEM);
 426         if (location->offset == (u64)-1) {
 427                 ret = find_and_setup_root(tree_root, fs_info,
 428                                           location->objectid, root);
 429                 if (ret) {
 430                         kfree(root);
 431                         return ERR_PTR(ret);
 432                 }
 433                 goto insert;
 434         }
 435
 436         __setup_root(tree_root->nodesize, tree_root->leafsize,
 437                      tree_root->sectorsize, tree_root->stripesize,
 438                      root, fs_info, location->objectid);
 439
 440         path = btrfs_alloc_path();
 441         BUG_ON(!path);
 442         ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
 443         if (ret != 0) {
 444                 if (ret > 0)
 445                         ret = -ENOENT;
 446                 goto out;
 447         }
 448         l = path->nodes[0];
 449         read_extent_buffer(l, &root->root_item,
 450                btrfs_item_ptr_offset(l, path->slots[0]),
 451                sizeof(root->root_item));
 452         memcpy(&root->root_key, location, sizeof(*location));
 453         ret = 0;
 454 out:
 455         btrfs_release_path(root, path);
 456         btrfs_free_path(path);
 457         if (ret) {
 458                 kfree(root);
 459                 return ERR_PTR(ret);
 460         }
 461         blocksize = btrfs_level_size(root, btrfs_root_level(&root->root_item));
 462         root->node = read_tree_block(root, btrfs_root_bytenr(&root->root_item),
 463                                      blocksize);
 464         BUG_ON(!root->node);
 465 insert:
 466         root->ref_cows = 1;
 467         ret = btrfs_find_highest_inode(root, &highest_inode);
 468         if (ret == 0) {
 469                 root->highest_inode = highest_inode;
 470                 root->last_inode_alloc = highest_inode;
 471         }
 472         return root;
 473 }
 474
 475 struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
 476                                               struct btrfs_key *location)
 477 {
 478         struct btrfs_root *root;
 479         int ret;
 480
 481         if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
 482                 return fs_info->tree_root;
 483         if (location->objectid == BTRFS_EXTENT_TREE_OBJECTID)
 484                 return fs_info->extent_root;
 485
 486         root = radix_tree_lookup(&fs_info->fs_roots_radix,
 487                                  (unsigned long)location->objectid);
 488         if (root)
 489                 return root;
 490
 491         root = btrfs_read_fs_root_no_radix(fs_info, location);
 492         if (IS_ERR(root))
 493                 return root;
 494         ret = radix_tree_insert(&fs_info->fs_roots_radix,
 495                                 (unsigned long)root->root_key.objectid,
 496                                 root);
 497         if (ret) {
 498                 free_extent_buffer(root->node);
 499                 kfree(root);
 500                 return ERR_PTR(ret);
 501         }
 502         ret = btrfs_find_dead_roots(fs_info->tree_root,
 503                                     root->root_key.objectid, root);
 504         BUG_ON(ret);
 505
 506         return root;
 507 }
 508
 509 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
 510                                       struct btrfs_key *location,
 511                                       const char *name, int namelen)
 512 {
 513         struct btrfs_root *root;
 514         int ret;
 515
 516         root = btrfs_read_fs_root_no_name(fs_info, location);
 517         if (!root)
 518                 return NULL;
 519
 520         if (root->in_sysfs)
 521                 return root;
 522
 523         ret = btrfs_set_root_name(root, name, namelen);
 524         if (ret) {
 525                 free_extent_buffer(root->node);
 526                 kfree(root);
 527                 return ERR_PTR(ret);
 528         }
 529
 530         ret = btrfs_sysfs_add_root(root);
 531         if (ret) {
 532                 free_extent_buffer(root->node);
 533                 kfree(root->name);
 534                 kfree(root);
 535                 return ERR_PTR(ret);
 536         }
 537         root->in_sysfs = 1;
 538         return root;
 539 }
 540 #if 0
 541 static int add_hasher(struct btrfs_fs_info *info, char *type) {
 542         struct btrfs_hasher *hasher;
 543
 544         hasher = kmalloc(sizeof(*hasher), GFP_NOFS);
 545         if (!hasher)
 546                 return -ENOMEM;
 547         hasher->hash_tfm = crypto_alloc_hash(type, 0, CRYPTO_ALG_ASYNC);
 548         if (!hasher->hash_tfm) {
 549                 kfree(hasher);
 550                 return -EINVAL;
 551         }
 552         spin_lock(&info->hash_lock);
 553         list_add(&hasher->list, &info->hashers);
 554         spin_unlock(&info->hash_lock);
 555         return 0;
 556 }
 557 #endif
 558 struct btrfs_root *open_ctree(struct super_block *sb)
 559 {
 560         u32 sectorsize;
 561         u32 nodesize;
 562         u32 leafsize;
 563         u32 blocksize;
 564         u32 stripesize;
 565         struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
 566                                                  GFP_NOFS);
 567         struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
 568                                                GFP_NOFS);
 569         struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
 570                                                 GFP_NOFS);
 571         int ret;
 572         int err = -EIO;
 573         struct btrfs_super_block *disk_super;
 574
 575         if (!extent_root || !tree_root || !fs_info) {
 576                 err = -ENOMEM;
 577                 goto fail;
 578         }
 579         INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
 580         INIT_LIST_HEAD(&fs_info->trans_list);
 581         INIT_LIST_HEAD(&fs_info->dead_roots);
 582         INIT_LIST_HEAD(&fs_info->hashers);
 583         spin_lock_init(&fs_info->hash_lock);
 584         spin_lock_init(&fs_info->delalloc_lock);
 585
 586         memset(&fs_info->super_kobj, 0, sizeof(fs_info->super_kobj));
 587         init_completion(&fs_info->kobj_unregister);
 588         sb_set_blocksize(sb, 4096);
 589         fs_info->running_transaction = NULL;
 590         fs_info->last_trans_committed = 0;
 591         fs_info->tree_root = tree_root;
 592         fs_info->extent_root = extent_root;
 593         fs_info->sb = sb;
 594         fs_info->mount_opt = 0;
 595         fs_info->max_extent = (u64)-1;
 596         fs_info->delalloc_bytes = 0;
 597         fs_info->btree_inode = new_inode(sb);
 598         fs_info->btree_inode->i_ino = 1;
 599         fs_info->btree_inode->i_nlink = 1;
 600         fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
 601         fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
 602         extent_map_tree_init(&BTRFS_I(fs_info->btree_inode)->extent_tree,
 603                              fs_info->btree_inode->i_mapping,
 604                              GFP_NOFS);
 605         BTRFS_I(fs_info->btree_inode)->extent_tree.ops = &btree_extent_map_ops;
 606
 607         extent_map_tree_init(&fs_info->free_space_cache,
 608                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 609         extent_map_tree_init(&fs_info->block_group_cache,
 610                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 611         extent_map_tree_init(&fs_info->pinned_extents,
 612                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 613         extent_map_tree_init(&fs_info->pending_del,
 614                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 615         extent_map_tree_init(&fs_info->extent_ins,
 616                              fs_info->btree_inode->i_mapping, GFP_NOFS);
 617         fs_info->do_barriers = 1;
 618         fs_info->closing = 0;
 619         fs_info->total_pinned = 0;
 620 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18)
 621         INIT_WORK(&fs_info->trans_work, btrfs_transaction_cleaner, fs_info);
 622 #else
 623         INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
 624 #endif
 625         BTRFS_I(fs_info->btree_inode)->root = tree_root;
 626         memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
 627                sizeof(struct btrfs_key));
 628         insert_inode_hash(fs_info->btree_inode);
 629         mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
 630
 631         mutex_init(&fs_info->trans_mutex);
 632         mutex_init(&fs_info->fs_mutex);
 633
 634 #if 0
 635         ret = add_hasher(fs_info, "crc32c");
 636         if (ret) {
 637                 printk("btrfs: failed hash setup, modprobe cryptomgr?\n");
 638                 err = -ENOMEM;
 639                 goto fail_iput;
 640         }
 641 #endif
 642         __setup_root(512, 512, 512, 512, tree_root,
 643                      fs_info, BTRFS_ROOT_TREE_OBJECTID);
 644
 645         fs_info->sb_buffer = read_tree_block(tree_root,
 646                                              BTRFS_SUPER_INFO_OFFSET,
 647                                              512);
 648
 649         if (!fs_info->sb_buffer)
 650                 goto fail_iput;
 651
 652         read_extent_buffer(fs_info->sb_buffer, &fs_info->super_copy, 0,
 653                            sizeof(fs_info->super_copy));
 654
 655         read_extent_buffer(fs_info->sb_buffer, fs_info->fsid,
 656                            (unsigned long)btrfs_super_fsid(fs_info->sb_buffer),
 657                            BTRFS_FSID_SIZE);
 658         disk_super = &fs_info->super_copy;
 659         if (!btrfs_super_root(disk_super))
 660                 goto fail_sb_buffer;
 661
 662         nodesize = btrfs_super_nodesize(disk_super);
 663         leafsize = btrfs_super_leafsize(disk_super);
 664         sectorsize = btrfs_super_sectorsize(disk_super);
 665         stripesize = btrfs_super_stripesize(disk_super);
 666         tree_root->nodesize = nodesize;
 667         tree_root->leafsize = leafsize;
 668         tree_root->sectorsize = sectorsize;
 669         tree_root->stripesize = stripesize;
 670         sb_set_blocksize(sb, sectorsize);
 671
 672         i_size_write(fs_info->btree_inode,
 673                      btrfs_super_total_bytes(disk_super));
 674
 675         if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
 676                     sizeof(disk_super->magic))) {
 677                 printk("btrfs: valid FS not found on %s\n", sb->s_id);
 678                 goto fail_sb_buffer;
 679         }
 680
 681         blocksize = btrfs_level_size(tree_root,
 682                                      btrfs_super_root_level(disk_super));
 683
 684         tree_root->node = read_tree_block(tree_root,
 685                                           btrfs_super_root(disk_super),
 686                                           blocksize);
 687         if (!tree_root->node)
 688                 goto fail_sb_buffer;
 689
 690         mutex_lock(&fs_info->fs_mutex);
 691
 692         ret = find_and_setup_root(tree_root, fs_info,
 693                                   BTRFS_EXTENT_TREE_OBJECTID, extent_root);
 694         if (ret) {
 695                 mutex_unlock(&fs_info->fs_mutex);
 696                 goto fail_tree_root;
 697         }
 698
 699         btrfs_read_block_groups(extent_root);
 700
 701         fs_info->generation = btrfs_super_generation(disk_super) + 1;
 702         mutex_unlock(&fs_info->fs_mutex);
 703         return tree_root;
 704
 705 fail_tree_root:
 706         free_extent_buffer(tree_root->node);
 707 fail_sb_buffer:
 708         free_extent_buffer(fs_info->sb_buffer);
 709 fail_iput:
 710         iput(fs_info->btree_inode);
 711 fail:
 712         kfree(extent_root);
 713         kfree(tree_root);
 714         kfree(fs_info);
 715         return ERR_PTR(err);
 716 }
 717
 718 int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
 719                       *root)
 720 {
 721         int ret;
 722         struct extent_buffer *super = root->fs_info->sb_buffer;
 723         struct inode *btree_inode = root->fs_info->btree_inode;
 724
 725         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, super);
 726         ret = sync_page_range_nolock(btree_inode, btree_inode->i_mapping,
 727                                      super->start, super->len);
 728         return ret;
 729 }
 730
 731 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
 732 {
 733         radix_tree_delete(&fs_info->fs_roots_radix,
 734                           (unsigned long)root->root_key.objectid);
 735         btrfs_sysfs_del_root(root);
 736         if (root->inode)
 737                 iput(root->inode);
 738         if (root->node)
 739                 free_extent_buffer(root->node);
 740         if (root->commit_root)
 741                 free_extent_buffer(root->commit_root);
 742         if (root->name)
 743                 kfree(root->name);
 744         kfree(root);
 745         return 0;
 746 }
 747
 748 static int del_fs_roots(struct btrfs_fs_info *fs_info)
 749 {
 750         int ret;
 751         struct btrfs_root *gang[8];
 752         int i;
 753
 754         while(1) {
 755                 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
 756                                              (void **)gang, 0,
 757                                              ARRAY_SIZE(gang));
 758                 if (!ret)
 759                         break;
 760                 for (i = 0; i < ret; i++)
 761                         btrfs_free_fs_root(fs_info, gang[i]);
 762         }
 763         return 0;
 764 }
 765
 766 int close_ctree(struct btrfs_root *root)
 767 {
 768         int ret;
 769         struct btrfs_trans_handle *trans;
 770         struct btrfs_fs_info *fs_info = root->fs_info;
 771
 772         fs_info->closing = 1;
 773         btrfs_transaction_flush_work(root);
 774         mutex_lock(&fs_info->fs_mutex);
 775         btrfs_defrag_dirty_roots(root->fs_info);
 776         trans = btrfs_start_transaction(root, 1);
 777         ret = btrfs_commit_transaction(trans, root);
 778         /* run commit again to  drop the original snapshot */
 779         trans = btrfs_start_transaction(root, 1);
 780         btrfs_commit_transaction(trans, root);
 781         ret = btrfs_write_and_wait_transaction(NULL, root);
 782         BUG_ON(ret);
 783         write_ctree_super(NULL, root);
 784         mutex_unlock(&fs_info->fs_mutex);
 785
 786         if (fs_info->extent_root->node)
 787                 free_extent_buffer(fs_info->extent_root->node);
 788
 789         if (fs_info->tree_root->node)
 790                 free_extent_buffer(fs_info->tree_root->node);
 791
 792         free_extent_buffer(fs_info->sb_buffer);
 793
 794         btrfs_free_block_groups(root->fs_info);
 795         del_fs_roots(fs_info);
 796
 797         filemap_write_and_wait(fs_info->btree_inode->i_mapping);
 798
 799         extent_map_tree_empty_lru(&fs_info->free_space_cache);
 800         extent_map_tree_empty_lru(&fs_info->block_group_cache);
 801         extent_map_tree_empty_lru(&fs_info->pinned_extents);
 802         extent_map_tree_empty_lru(&fs_info->pending_del);
 803         extent_map_tree_empty_lru(&fs_info->extent_ins);
 804         extent_map_tree_empty_lru(&BTRFS_I(fs_info->btree_inode)->extent_tree);
 805
 806         truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
 807
 808         iput(fs_info->btree_inode);
 809 #if 0
 810         while(!list_empty(&fs_info->hashers)) {
 811                 struct btrfs_hasher *hasher;
 812                 hasher = list_entry(fs_info->hashers.next, struct btrfs_hasher,
 813                                     hashers);
 814                 list_del(&hasher->hashers);
 815                 crypto_free_hash(&fs_info->hash_tfm);
 816                 kfree(hasher);
 817         }
 818 #endif
 819         kfree(fs_info->extent_root);
 820         kfree(fs_info->tree_root);
 821         return 0;
 822 }
 823
 824 int btrfs_buffer_uptodate(struct extent_buffer *buf)
 825 {
 826         struct inode *btree_inode = buf->first_page->mapping->host;
 827         return extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree, buf);
 828 }
 829
 830 int btrfs_set_buffer_uptodate(struct extent_buffer *buf)
 831 {
 832         struct inode *btree_inode = buf->first_page->mapping->host;
 833         return set_extent_buffer_uptodate(&BTRFS_I(btree_inode)->extent_tree,
 834                                           buf);
 835 }
 836
 837 void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
 838 {
 839         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 840         u64 transid = btrfs_header_generation(buf);
 841         struct inode *btree_inode = root->fs_info->btree_inode;
 842
 843         if (transid != root->fs_info->generation) {
 844                 printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
 845                         (unsigned long long)buf->start,
 846                         transid, root->fs_info->generation);
 847                 WARN_ON(1);
 848         }
 849         set_extent_buffer_dirty(&BTRFS_I(btree_inode)->extent_tree, buf);
 850 }
 851
 852 void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr)
 853 {
 854         balance_dirty_pages_ratelimited_nr(
 855                         root->fs_info->btree_inode->i_mapping, 1);
 856 }
 857
 858 void btrfs_set_buffer_defrag(struct extent_buffer *buf)
 859 {
 860         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 861         struct inode *btree_inode = root->fs_info->btree_inode;
 862         set_extent_bits(&BTRFS_I(btree_inode)->extent_tree, buf->start,
 863                         buf->start + buf->len - 1, EXTENT_DEFRAG, GFP_NOFS);
 864 }
 865
 866 void btrfs_set_buffer_defrag_done(struct extent_buffer *buf)
 867 {
 868         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 869         struct inode *btree_inode = root->fs_info->btree_inode;
 870         set_extent_bits(&BTRFS_I(btree_inode)->extent_tree, buf->start,
 871                         buf->start + buf->len - 1, EXTENT_DEFRAG_DONE,
 872                         GFP_NOFS);
 873 }
 874
 875 int btrfs_buffer_defrag(struct extent_buffer *buf)
 876 {
 877         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 878         struct inode *btree_inode = root->fs_info->btree_inode;
 879         return test_range_bit(&BTRFS_I(btree_inode)->extent_tree,
 880                      buf->start, buf->start + buf->len - 1, EXTENT_DEFRAG, 0);
 881 }
 882
 883 int btrfs_buffer_defrag_done(struct extent_buffer *buf)
 884 {
 885         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 886         struct inode *btree_inode = root->fs_info->btree_inode;
 887         return test_range_bit(&BTRFS_I(btree_inode)->extent_tree,
 888                      buf->start, buf->start + buf->len - 1,
 889                      EXTENT_DEFRAG_DONE, 0);
 890 }
 891
 892 int btrfs_clear_buffer_defrag_done(struct extent_buffer *buf)
 893 {
 894         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 895         struct inode *btree_inode = root->fs_info->btree_inode;
 896         return clear_extent_bits(&BTRFS_I(btree_inode)->extent_tree,
 897                      buf->start, buf->start + buf->len - 1,
 898                      EXTENT_DEFRAG_DONE, GFP_NOFS);
 899 }
 900
 901 int btrfs_clear_buffer_defrag(struct extent_buffer *buf)
 902 {
 903         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 904         struct inode *btree_inode = root->fs_info->btree_inode;
 905         return clear_extent_bits(&BTRFS_I(btree_inode)->extent_tree,
 906                      buf->start, buf->start + buf->len - 1,
 907                      EXTENT_DEFRAG, GFP_NOFS);
 908 }
 909
 910 int btrfs_read_buffer(struct extent_buffer *buf)
 911 {
 912         struct btrfs_root *root = BTRFS_I(buf->first_page->mapping->host)->root;
 913         struct inode *btree_inode = root->fs_info->btree_inode;
 914         return read_extent_buffer_pages(&BTRFS_I(btree_inode)->extent_tree,
 915                                         buf, 0, 1);
 916 }
 917
 918 static struct extent_map_ops btree_extent_map_ops = {
 919         .writepage_io_hook = btree_writepage_io_hook,
 920 };