81 строка
2.1 KiB
C
81 строка
2.1 KiB
C
/*
|
|
* 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 "ctree.h"
|
|
#include "disk-io.h"
|
|
#include "transaction.h"
|
|
|
|
int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid)
|
|
{
|
|
struct btrfs_path *path;
|
|
int ret;
|
|
struct extent_buffer *l;
|
|
struct btrfs_key search_key;
|
|
struct btrfs_key found_key;
|
|
int slot;
|
|
|
|
path = btrfs_alloc_path();
|
|
BUG_ON(!path);
|
|
|
|
search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
|
|
search_key.type = -1;
|
|
search_key.offset = (u64)-1;
|
|
ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
|
|
if (ret < 0)
|
|
goto error;
|
|
BUG_ON(ret == 0);
|
|
if (path->slots[0] > 0) {
|
|
slot = path->slots[0] - 1;
|
|
l = path->nodes[0];
|
|
btrfs_item_key_to_cpu(l, &found_key, slot);
|
|
*objectid = max_t(u64, found_key.objectid,
|
|
BTRFS_FIRST_FREE_OBJECTID - 1);
|
|
} else {
|
|
*objectid = BTRFS_FIRST_FREE_OBJECTID - 1;
|
|
}
|
|
ret = 0;
|
|
error:
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
|
|
struct btrfs_root *root,
|
|
u64 dirid, u64 *objectid)
|
|
{
|
|
int ret;
|
|
mutex_lock(&root->objectid_mutex);
|
|
|
|
if (unlikely(root->highest_objectid < BTRFS_FIRST_FREE_OBJECTID)) {
|
|
ret = btrfs_find_highest_inode(root, &root->highest_objectid);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
if (unlikely(root->highest_objectid >= BTRFS_LAST_FREE_OBJECTID)) {
|
|
ret = -ENOSPC;
|
|
goto out;
|
|
}
|
|
|
|
*objectid = ++root->highest_objectid;
|
|
ret = 0;
|
|
out:
|
|
mutex_unlock(&root->objectid_mutex);
|
|
return ret;
|
|
}
|