mirror of
https://github.com/kdave/btrfs-progs
synced 2024-12-27 08:32:20 +00:00
775 lines
20 KiB
C
775 lines
20 KiB
C
/*
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* Copyright (C) 2007 Oracle. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include "kerncompat.h"
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#include "radix-tree.h"
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#include "ctree.h"
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#include "disk-io.h"
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#include "print-tree.h"
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#include "transaction.h"
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static int finish_current_insert(struct btrfs_trans_handle *trans, struct
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btrfs_root *extent_root);
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static int run_pending(struct btrfs_trans_handle *trans, struct btrfs_root
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*extent_root);
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static int inc_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
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*root, u64 bytenr, u32 blocksize)
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{
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struct btrfs_path path;
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int ret;
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struct btrfs_key key;
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struct btrfs_leaf *l;
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struct btrfs_extent_item *item;
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u32 refs;
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btrfs_init_path(&path);
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key.objectid = bytenr;
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btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
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key.offset = blocksize;
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ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, &path,
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0, 1);
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if (ret != 0)
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BUG();
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BUG_ON(ret != 0);
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l = &path.nodes[0]->leaf;
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item = btrfs_item_ptr(l, path.slots[0], struct btrfs_extent_item);
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refs = btrfs_extent_refs(item);
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btrfs_set_extent_refs(item, refs + 1);
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BUG_ON(list_empty(&path.nodes[0]->dirty));
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btrfs_release_path(root->fs_info->extent_root, &path);
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finish_current_insert(trans, root->fs_info->extent_root);
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run_pending(trans, root->fs_info->extent_root);
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return 0;
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}
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static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
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*root, u64 bytenr, u32 blocksize, u32 *refs)
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{
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struct btrfs_path path;
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int ret;
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struct btrfs_key key;
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struct btrfs_leaf *l;
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struct btrfs_extent_item *item;
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btrfs_init_path(&path);
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key.objectid = bytenr;
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key.offset = blocksize;
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btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
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ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, &path,
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0, 0);
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if (ret != 0)
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BUG();
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l = &path.nodes[0]->leaf;
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item = btrfs_item_ptr(l, path.slots[0], struct btrfs_extent_item);
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*refs = btrfs_extent_refs(item);
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btrfs_release_path(root->fs_info->extent_root, &path);
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return 0;
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}
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int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
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struct btrfs_buffer *buf)
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{
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u64 bytenr;
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int i;
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if (!root->ref_cows)
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return 0;
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if (btrfs_is_leaf(&buf->node))
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return 0;
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for (i = 0; i < btrfs_header_nritems(&buf->node.header); i++) {
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bytenr = btrfs_node_blockptr(&buf->node, i);
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inc_block_ref(trans, root, bytenr, root->nodesize);
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}
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return 0;
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}
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static int write_one_cache_group(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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struct btrfs_path *path,
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struct btrfs_block_group_cache *cache)
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{
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int ret;
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int pending_ret;
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struct btrfs_root *extent_root = root->fs_info->extent_root;
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struct btrfs_block_group_item *bi;
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ret = btrfs_search_slot(trans, root->fs_info->extent_root,
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&cache->key, path, 0, 1);
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BUG_ON(ret);
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bi = btrfs_item_ptr(&path->nodes[0]->leaf, path->slots[0],
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struct btrfs_block_group_item);
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memcpy(bi, &cache->item, sizeof(*bi));
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dirty_tree_block(trans, extent_root, path->nodes[0]);
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btrfs_release_path(extent_root, path);
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finish_current_insert(trans, root);
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pending_ret = run_pending(trans, root);
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if (ret)
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return ret;
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if (pending_ret)
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return pending_ret;
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return 0;
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}
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int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
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struct btrfs_root *root)
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{
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struct btrfs_block_group_cache *bg;
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struct cache_extent *cache;
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int err = 0;
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int werr = 0;
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struct cache_tree *bg_cache = &root->fs_info->block_group_cache;
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struct btrfs_path path;
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btrfs_init_path(&path);
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u64 start = 0;
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while(1) {
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cache = find_first_cache_extent(bg_cache, start);
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if (!cache)
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break;
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bg = container_of(cache, struct btrfs_block_group_cache,
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cache);
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start = cache->start + cache->size;
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if (bg->dirty) {
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err = write_one_cache_group(trans, root,
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&path, bg);
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if (err)
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werr = err;
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}
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bg->dirty = 0;
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}
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return werr;
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}
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static int update_block_group(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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u64 bytenr, u64 num, int alloc)
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{
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struct btrfs_block_group_cache *bg;
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struct cache_extent *cache;
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struct btrfs_fs_info *info = root->fs_info;
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u64 total = num;
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u64 old_val;
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u64 byte_in_group;
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while(total) {
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cache = find_first_cache_extent(&info->block_group_cache,
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bytenr);
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if (!cache)
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return -1;
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bg = container_of(cache, struct btrfs_block_group_cache,
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cache);
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bg->dirty = 1;
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byte_in_group = bytenr - bg->key.objectid;
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old_val = btrfs_block_group_used(&bg->item);
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if (total > bg->key.offset - byte_in_group)
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num = bg->key.offset - byte_in_group;
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else
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num = total;
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total -= num;
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bytenr += num;
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if (alloc)
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old_val += num;
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else
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old_val -= num;
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btrfs_set_block_group_used(&bg->item, old_val);
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}
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return 0;
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}
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int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct
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btrfs_root *root)
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{
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u64 first = 0;
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struct cache_extent *pe;
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struct cache_extent *next;
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pe = find_first_cache_extent(&root->fs_info->pinned_tree, 0);
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if (pe)
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first = pe->start;
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while(pe) {
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next = next_cache_extent(pe);
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remove_cache_extent(&root->fs_info->pinned_tree, pe);
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free_cache_extent(pe);
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pe = next;
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}
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root->fs_info->last_insert.objectid = first;
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root->fs_info->last_insert.offset = 0;
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return 0;
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}
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static int finish_current_insert(struct btrfs_trans_handle *trans, struct
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btrfs_root *extent_root)
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{
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struct btrfs_key ins;
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struct btrfs_extent_item extent_item;
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int ret;
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struct btrfs_fs_info *info = extent_root->fs_info;
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struct cache_extent *pe;
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struct cache_extent *next;
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struct cache_tree *pending_tree = &info->pending_tree;
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btrfs_set_extent_refs(&extent_item, 1);
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btrfs_set_extent_owner(&extent_item, extent_root->root_key.objectid);
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ins.offset = 1;
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btrfs_set_key_type(&ins, BTRFS_EXTENT_ITEM_KEY);
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pe = find_first_cache_extent(pending_tree, 0);
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while(pe) {
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ins.offset = pe->size;
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ins.objectid = pe->start;
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remove_cache_extent(pending_tree, pe);
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next = next_cache_extent(pe);
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if (!next)
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next = find_first_cache_extent(pending_tree, 0);
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free_cache_extent(pe);
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pe = next;
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ret = btrfs_insert_item(trans, extent_root, &ins, &extent_item,
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sizeof(extent_item));
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if (ret) {
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btrfs_print_tree(extent_root, extent_root->node);
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}
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BUG_ON(ret);
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}
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return 0;
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}
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/*
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* remove an extent from the root, returns 0 on success
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*/
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static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
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*root, u64 bytenr, u64 num_bytes, int pin)
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{
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struct btrfs_path path;
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struct btrfs_key key;
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struct btrfs_fs_info *info = root->fs_info;
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struct btrfs_root *extent_root = info->extent_root;
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int ret;
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struct btrfs_extent_item *ei;
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u32 refs;
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key.objectid = bytenr;
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btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
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key.offset = num_bytes;
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btrfs_init_path(&path);
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ret = btrfs_search_slot(trans, extent_root, &key, &path, -1, 1);
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if (ret) {
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btrfs_print_tree(extent_root, extent_root->node);
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printf("failed to find %llu\n",
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(unsigned long long)key.objectid);
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BUG();
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}
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ei = btrfs_item_ptr(&path.nodes[0]->leaf, path.slots[0],
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struct btrfs_extent_item);
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BUG_ON(ei->refs == 0);
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refs = btrfs_extent_refs(ei) - 1;
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btrfs_set_extent_refs(ei, refs);
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if (refs == 0) {
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u64 super_bytes_used, root_bytes_used;
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if (pin) {
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int err;
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err = insert_cache_extent(&info->pinned_tree,
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bytenr, num_bytes);
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BUG_ON(err);
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}
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super_bytes_used = btrfs_super_bytes_used(info->disk_super);
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btrfs_set_super_bytes_used(info->disk_super,
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super_bytes_used - num_bytes);
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root_bytes_used = btrfs_root_bytes_used(&root->root_item);
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btrfs_set_root_bytes_used(&root->root_item,
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root_bytes_used - num_bytes);
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ret = btrfs_del_item(trans, extent_root, &path);
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if (!pin && extent_root->fs_info->last_insert.objectid >
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bytenr)
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extent_root->fs_info->last_insert.objectid = bytenr;
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if (ret)
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BUG();
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ret = update_block_group(trans, root, bytenr, num_bytes, 0);
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BUG_ON(ret);
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}
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btrfs_release_path(extent_root, &path);
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finish_current_insert(trans, extent_root);
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return ret;
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}
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/*
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* find all the blocks marked as pending in the radix tree and remove
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* them from the extent map
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*/
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static int del_pending_extents(struct btrfs_trans_handle *trans, struct
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btrfs_root *extent_root)
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{
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int ret;
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struct cache_extent *pe;
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struct cache_extent *next;
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struct cache_tree *del_pending = &extent_root->fs_info->del_pending;
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pe = find_first_cache_extent(del_pending, 0);
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while(pe) {
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remove_cache_extent(del_pending, pe);
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ret = __free_extent(trans, extent_root,
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pe->start, pe->size, 1);
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BUG_ON(ret);
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next = next_cache_extent(pe);
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if (!next)
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next = find_first_cache_extent(del_pending, 0);
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free_cache_extent(pe);
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pe = next;
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}
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return 0;
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}
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static int run_pending(struct btrfs_trans_handle *trans, struct btrfs_root
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*extent_root)
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{
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del_pending_extents(trans, extent_root);
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return 0;
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}
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/*
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* remove an extent from the root, returns 0 on success
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*/
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int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
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*root, u64 bytenr, u64 num_bytes, int pin)
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{
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struct btrfs_root *extent_root = root->fs_info->extent_root;
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int pending_ret;
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int ret;
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if (root == extent_root) {
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ret = insert_cache_extent(&root->fs_info->del_pending,
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bytenr, num_bytes);
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BUG_ON(ret);
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return 0;
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}
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ret = __free_extent(trans, root, bytenr, num_bytes, pin);
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pending_ret = run_pending(trans, root->fs_info->extent_root);
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return ret ? ret : pending_ret;
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}
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/*
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* walks the btree of allocated extents and find a hole of a given size.
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* The key ins is changed to record the hole:
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* ins->objectid == block start
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* ins->flags = BTRFS_EXTENT_ITEM_KEY
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* ins->offset == number of blocks
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* Any available blocks before search_start are skipped.
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*/
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static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
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*orig_root, u64 total_needed, u64 search_start,
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u64 search_end, struct btrfs_key *ins)
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{
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struct btrfs_path path;
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struct btrfs_key key;
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int ret;
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u64 hole_size = 0;
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int slot = 0;
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u64 last_byte = 0;
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int start_found;
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struct btrfs_leaf *l;
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struct btrfs_root * root = orig_root->fs_info->extent_root;
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if (root->fs_info->last_insert.objectid > search_start)
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search_start = root->fs_info->last_insert.objectid;
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btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
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check_failed:
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btrfs_init_path(&path);
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ins->objectid = search_start;
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ins->offset = 0;
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start_found = 0;
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ret = btrfs_search_slot(trans, root, ins, &path, 0, 0);
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if (ret < 0)
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goto error;
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if (path.slots[0] > 0)
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path.slots[0]--;
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while (1) {
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l = &path.nodes[0]->leaf;
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slot = path.slots[0];
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if (slot >= btrfs_header_nritems(&l->header)) {
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ret = btrfs_next_leaf(root, &path);
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if (ret == 0)
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continue;
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if (ret < 0)
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goto error;
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if (!start_found) {
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ins->objectid = search_start;
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ins->offset = (u64)-1 - search_start;
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start_found = 1;
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goto check_pending;
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}
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ins->objectid = last_byte > search_start ?
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last_byte : search_start;
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ins->offset = (u64)-1 - ins->objectid;
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goto check_pending;
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}
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btrfs_disk_key_to_cpu(&key, &l->items[slot].key);
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if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY)
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goto next;
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if (key.objectid >= search_start) {
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if (start_found) {
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if (last_byte < search_start)
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last_byte = search_start;
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hole_size = key.objectid - last_byte;
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if (hole_size > total_needed) {
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ins->objectid = last_byte;
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ins->offset = hole_size;
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goto check_pending;
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}
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}
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}
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start_found = 1;
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last_byte = key.objectid + key.offset;
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next:
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path.slots[0]++;
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}
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// FIXME -ENOSPC
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check_pending:
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/* we have to make sure we didn't find an extent that has already
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* been allocated by the map tree or the original allocation
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*/
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btrfs_release_path(root, &path);
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BUG_ON(ins->objectid < search_start);
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if (find_cache_extent(&root->fs_info->pinned_tree,
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ins->objectid, total_needed)) {
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search_start = ins->objectid + total_needed;
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goto check_failed;
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}
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if (find_cache_extent(&root->fs_info->pending_tree,
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ins->objectid, total_needed)) {
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search_start = ins->objectid + total_needed;
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goto check_failed;
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}
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root->fs_info->last_insert.objectid = ins->objectid;
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ins->offset = total_needed;
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return 0;
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error:
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btrfs_release_path(root, &path);
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return ret;
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}
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/*
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* finds a free extent and does all the dirty work required for allocation
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* returns the key for the extent through ins, and a tree buffer for
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* the first block of the extent through buf.
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*
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* returns 0 if everything worked, non-zero otherwise.
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*/
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static int alloc_extent(struct btrfs_trans_handle *trans,
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struct btrfs_root *root, u64 owner,
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u64 num_bytes, u64 search_start,
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u64 search_end, struct btrfs_key *ins)
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{
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int ret;
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int pending_ret;
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u64 super_bytes_used, root_bytes_used;
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struct btrfs_fs_info *info = root->fs_info;
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struct btrfs_root *extent_root = info->extent_root;
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struct btrfs_extent_item extent_item;
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btrfs_set_extent_refs(&extent_item, 1);
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btrfs_set_extent_owner(&extent_item, owner);
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ret = find_free_extent(trans, root, num_bytes, search_start,
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search_end, ins);
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if (ret)
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return ret;
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super_bytes_used = btrfs_super_bytes_used(info->disk_super);
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btrfs_set_super_bytes_used(info->disk_super, super_bytes_used +
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num_bytes);
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root_bytes_used = btrfs_root_bytes_used(&root->root_item);
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btrfs_set_root_bytes_used(&root->root_item, root_bytes_used +
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num_bytes);
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if (root == extent_root) {
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ret = insert_cache_extent(&root->fs_info->pending_tree,
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ins->objectid, ins->offset);
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BUG_ON(ret);
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return 0;
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}
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ret = btrfs_insert_item(trans, extent_root, ins, &extent_item,
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sizeof(extent_item));
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finish_current_insert(trans, extent_root);
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pending_ret = run_pending(trans, extent_root);
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if (ret)
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return ret;
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if (pending_ret)
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return pending_ret;
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return 0;
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}
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/*
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* helper function to allocate a block for a given tree
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* returns the tree buffer or NULL.
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*/
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struct btrfs_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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u32 blocksize)
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{
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struct btrfs_key ins;
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int ret;
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struct btrfs_buffer *buf;
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ret = alloc_extent(trans, root, root->root_key.objectid,
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blocksize, 0, (unsigned long)-1, &ins);
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if (ret) {
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BUG();
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return NULL;
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}
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ret = update_block_group(trans, root, ins.objectid, ins.offset, 1);
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buf = find_tree_block(root, ins.objectid, blocksize);
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btrfs_set_header_generation(&buf->node.header,
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root->root_key.offset + 1);
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btrfs_set_header_bytenr(&buf->node.header, buf->bytenr);
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memcpy(buf->node.header.fsid, root->fs_info->disk_super->fsid,
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sizeof(buf->node.header.fsid));
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dirty_tree_block(trans, root, buf);
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return buf;
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}
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/*
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* helper function for drop_snapshot, this walks down the tree dropping ref
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* counts as it goes.
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*/
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static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root
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*root, struct btrfs_path *path, int *level)
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{
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struct btrfs_buffer *next;
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struct btrfs_buffer *cur;
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u64 bytenr;
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int ret;
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u32 refs;
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ret = lookup_block_ref(trans, root, path->nodes[*level]->bytenr,
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btrfs_level_size(root, *level), &refs);
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BUG_ON(ret);
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if (refs > 1)
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goto out;
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/*
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* walk down to the last node level and free all the leaves
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*/
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while(*level > 0) {
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u32 size = btrfs_level_size(root, *level - 1);
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|
|
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cur = path->nodes[*level];
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if (path->slots[*level] >=
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btrfs_header_nritems(&cur->node.header))
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break;
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bytenr = btrfs_node_blockptr(&cur->node, path->slots[*level]);
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ret = lookup_block_ref(trans, root, bytenr, size, &refs);
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if (refs != 1 || *level == 1) {
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path->slots[*level]++;
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ret = btrfs_free_extent(trans, root, bytenr, size, 1);
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BUG_ON(ret);
|
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continue;
|
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}
|
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BUG_ON(ret);
|
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next = read_tree_block(root, bytenr, size);
|
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if (path->nodes[*level-1])
|
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btrfs_block_release(root, path->nodes[*level-1]);
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path->nodes[*level-1] = next;
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*level = btrfs_header_level(&next->node.header);
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path->slots[*level] = 0;
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}
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out:
|
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ret = btrfs_free_extent(trans, root, path->nodes[*level]->bytenr,
|
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btrfs_level_size(root, *level), 1);
|
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btrfs_block_release(root, path->nodes[*level]);
|
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path->nodes[*level] = NULL;
|
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*level += 1;
|
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BUG_ON(ret);
|
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return 0;
|
|
}
|
|
|
|
/*
|
|
* helper for dropping snapshots. This walks back up the tree in the path
|
|
* to find the first node higher up where we haven't yet gone through
|
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* all the slots
|
|
*/
|
|
static int walk_up_tree(struct btrfs_trans_handle *trans, struct btrfs_root
|
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*root, struct btrfs_path *path, int *level)
|
|
{
|
|
int i;
|
|
int slot;
|
|
int ret;
|
|
for(i = *level; i < BTRFS_MAX_LEVEL - 1 && path->nodes[i]; i++) {
|
|
slot = path->slots[i];
|
|
if (slot <
|
|
btrfs_header_nritems(&path->nodes[i]->node.header)- 1) {
|
|
path->slots[i]++;
|
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*level = i;
|
|
return 0;
|
|
} else {
|
|
ret = btrfs_free_extent(trans, root,
|
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path->nodes[*level]->bytenr,
|
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btrfs_level_size(root, *level), 1);
|
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btrfs_block_release(root, path->nodes[*level]);
|
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path->nodes[*level] = NULL;
|
|
*level = i + 1;
|
|
BUG_ON(ret);
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* drop the reference count on the tree rooted at 'snap'. This traverses
|
|
* the tree freeing any blocks that have a ref count of zero after being
|
|
* decremented.
|
|
*/
|
|
int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
|
|
*root, struct btrfs_buffer *snap)
|
|
{
|
|
int ret = 0;
|
|
int wret;
|
|
int level;
|
|
struct btrfs_path path;
|
|
int i;
|
|
int orig_level;
|
|
|
|
btrfs_init_path(&path);
|
|
|
|
level = btrfs_header_level(&snap->node.header);
|
|
orig_level = level;
|
|
path.nodes[level] = snap;
|
|
path.slots[level] = 0;
|
|
while(1) {
|
|
wret = walk_down_tree(trans, root, &path, &level);
|
|
if (wret > 0)
|
|
break;
|
|
if (wret < 0)
|
|
ret = wret;
|
|
|
|
wret = walk_up_tree(trans, root, &path, &level);
|
|
if (wret > 0)
|
|
break;
|
|
if (wret < 0)
|
|
ret = wret;
|
|
}
|
|
for (i = 0; i <= orig_level; i++) {
|
|
if (path.nodes[i]) {
|
|
btrfs_block_release(root, path.nodes[i]);
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_free_block_groups(struct btrfs_fs_info *info)
|
|
{
|
|
struct btrfs_block_group_cache *bg;
|
|
struct cache_extent *cache;
|
|
|
|
while(1) {
|
|
cache = find_first_cache_extent(&info->block_group_cache, 0);
|
|
if (!cache)
|
|
break;
|
|
bg = container_of(cache, struct btrfs_block_group_cache,
|
|
cache);
|
|
remove_cache_extent(&info->block_group_cache, cache);
|
|
free(bg);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int btrfs_read_block_groups(struct btrfs_root *root)
|
|
{
|
|
struct btrfs_path path;
|
|
int ret;
|
|
int err = 0;
|
|
struct btrfs_block_group_item *bi;
|
|
struct btrfs_block_group_cache *bg;
|
|
struct cache_tree *bg_cache;
|
|
struct btrfs_key key;
|
|
struct btrfs_key found_key;
|
|
struct btrfs_leaf *leaf;
|
|
u64 group_size = BTRFS_BLOCK_GROUP_SIZE;
|
|
|
|
root = root->fs_info->extent_root;
|
|
bg_cache = &root->fs_info->block_group_cache;
|
|
key.objectid = 0;
|
|
key.offset = group_size;
|
|
btrfs_set_key_type(&key, BTRFS_BLOCK_GROUP_ITEM_KEY);
|
|
btrfs_init_path(&path);
|
|
|
|
while(1) {
|
|
ret = btrfs_search_slot(NULL, root->fs_info->extent_root,
|
|
&key, &path, 0, 0);
|
|
if (ret != 0) {
|
|
err = ret;
|
|
break;
|
|
}
|
|
leaf = &path.nodes[0]->leaf;
|
|
btrfs_disk_key_to_cpu(&found_key,
|
|
&leaf->items[path.slots[0]].key);
|
|
bg = malloc(sizeof(*bg));
|
|
if (!bg) {
|
|
err = -1;
|
|
break;
|
|
}
|
|
bi = btrfs_item_ptr(leaf, path.slots[0],
|
|
struct btrfs_block_group_item);
|
|
memcpy(&bg->item, bi, sizeof(*bi));
|
|
memcpy(&bg->key, &found_key, sizeof(found_key));
|
|
key.objectid = found_key.objectid + found_key.offset;
|
|
btrfs_release_path(root, &path);
|
|
bg->cache.start = found_key.objectid;
|
|
bg->cache.size = found_key.offset;
|
|
ret = insert_existing_cache_extent(bg_cache, &bg->cache);
|
|
BUG_ON(ret);
|
|
if (key.objectid >=
|
|
btrfs_super_total_bytes(root->fs_info->disk_super))
|
|
break;
|
|
}
|
|
btrfs_release_path(root, &path);
|
|
return 0;
|
|
}
|
|
|
|
int btrfs_insert_block_group(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root,
|
|
struct btrfs_key *key,
|
|
struct btrfs_block_group_item *bi)
|
|
{
|
|
int ret;
|
|
int pending_ret;
|
|
|
|
root = root->fs_info->extent_root;
|
|
ret = btrfs_insert_item(trans, root, key, bi, sizeof(*bi));
|
|
finish_current_insert(trans, root);
|
|
pending_ret = run_pending(trans, root);
|
|
if (ret)
|
|
return ret;
|
|
if (pending_ret)
|
|
return pending_ret;
|
|
return ret;
|
|
}
|