mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/kdave/btrfs-progs.git
synced 2024-11-16 08:44:31 +08:00
90 lines
2.0 KiB
C
90 lines
2.0 KiB
C
#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;
|
|
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;
|
|
}
|