blob: ad9e943d6fdbd9279415e0dffaa280e038170a66 [file] [log] [blame]
/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include "kerncompat.h"
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
/*
* walks the btree of allocated inodes and find a hole.
*/
int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 dirid, u64 *objectid)
{
struct btrfs_path path;
struct btrfs_key key;
int ret;
u64 hole_size = 0;
int slot = 0;
u64 last_ino = 0;
int start_found;
struct btrfs_leaf *l;
struct btrfs_key search_key;
u64 search_start = dirid;
if (root->fs_info->last_inode_alloc_dirid == dirid)
search_start = root->fs_info->last_inode_alloc;
if (search_start < BTRFS_FIRST_FREE_OBJECTID)
search_start = BTRFS_FIRST_FREE_OBJECTID;
search_key.objectid = search_start;
search_key.flags = 0;
search_key.offset = 0;
btrfs_init_path(&path);
start_found = 0;
ret = btrfs_search_slot(trans, root, &search_key, &path, 0, 0);
if (ret < 0)
goto error;
if (path.slots[0] > 0)
path.slots[0]--;
while (1) {
l = &path.nodes[0]->leaf;
slot = path.slots[0];
if (slot >= btrfs_header_nritems(&l->header)) {
ret = btrfs_next_leaf(root, &path);
if (ret == 0)
continue;
if (ret < 0)
goto error;
if (!start_found) {
*objectid = search_start;
start_found = 1;
goto found;
}
*objectid = last_ino > search_start ?
last_ino : search_start;
goto found;
}
btrfs_disk_key_to_cpu(&key, &l->items[slot].key);
if (key.objectid >= search_start) {
if (start_found) {
if (last_ino < search_start)
last_ino = search_start;
hole_size = key.objectid - last_ino;
if (hole_size > 0) {
*objectid = last_ino;
goto found;
}
}
}
start_found = 1;
last_ino = key.objectid + 1;
path.slots[0]++;
}
// FIXME -ENOSPC
found:
root->fs_info->last_inode_alloc = *objectid;
root->fs_info->last_inode_alloc_dirid = dirid;
btrfs_release_path(root, &path);
BUG_ON(*objectid < search_start);
return 0;
error:
btrfs_release_path(root, &path);
return ret;
}