mirror of
https://github.com/sheumann/hush.git
synced 2024-08-20 04:28:57 +00:00
175 lines
3.6 KiB
C
175 lines
3.6 KiB
C
/* vi: set sw=4 ts=4: */
|
|
/*
|
|
* alloc.c --- allocate new inodes, blocks for ext2fs
|
|
*
|
|
* Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
|
|
*
|
|
* %Begin-Header%
|
|
* This file may be redistributed under the terms of the GNU Public
|
|
* License.
|
|
* %End-Header%
|
|
*
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#if HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
#include <time.h>
|
|
#include <string.h>
|
|
#if HAVE_SYS_STAT_H
|
|
#include <sys/stat.h>
|
|
#endif
|
|
#if HAVE_SYS_TYPES_H
|
|
#include <sys/types.h>
|
|
#endif
|
|
|
|
#include "ext2_fs.h"
|
|
#include "ext2fs.h"
|
|
|
|
/*
|
|
* Right now, just search forward from the parent directory's block
|
|
* group to find the next free inode.
|
|
*
|
|
* Should have a special policy for directories.
|
|
*/
|
|
errcode_t ext2fs_new_inode(ext2_filsys fs, ext2_ino_t dir,
|
|
int mode EXT2FS_ATTR((unused)),
|
|
ext2fs_inode_bitmap map, ext2_ino_t *ret)
|
|
{
|
|
ext2_ino_t dir_group = 0;
|
|
ext2_ino_t i;
|
|
ext2_ino_t start_inode;
|
|
|
|
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
|
|
|
if (!map)
|
|
map = fs->inode_map;
|
|
if (!map)
|
|
return EXT2_ET_NO_INODE_BITMAP;
|
|
|
|
if (dir > 0)
|
|
dir_group = (dir - 1) / EXT2_INODES_PER_GROUP(fs->super);
|
|
|
|
start_inode = (dir_group * EXT2_INODES_PER_GROUP(fs->super)) + 1;
|
|
if (start_inode < EXT2_FIRST_INODE(fs->super))
|
|
start_inode = EXT2_FIRST_INODE(fs->super);
|
|
i = start_inode;
|
|
|
|
do {
|
|
if (!ext2fs_fast_test_inode_bitmap(map, i))
|
|
break;
|
|
i++;
|
|
if (i > fs->super->s_inodes_count)
|
|
i = EXT2_FIRST_INODE(fs->super);
|
|
} while (i != start_inode);
|
|
|
|
if (ext2fs_test_inode_bitmap(map, i))
|
|
return EXT2_ET_INODE_ALLOC_FAIL;
|
|
*ret = i;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Stupid algorithm --- we now just search forward starting from the
|
|
* goal. Should put in a smarter one someday....
|
|
*/
|
|
errcode_t ext2fs_new_block(ext2_filsys fs, blk_t goal,
|
|
ext2fs_block_bitmap map, blk_t *ret)
|
|
{
|
|
blk_t i;
|
|
|
|
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
|
|
|
if (!map)
|
|
map = fs->block_map;
|
|
if (!map)
|
|
return EXT2_ET_NO_BLOCK_BITMAP;
|
|
if (!goal || (goal >= fs->super->s_blocks_count))
|
|
goal = fs->super->s_first_data_block;
|
|
i = goal;
|
|
do {
|
|
if (!ext2fs_fast_test_block_bitmap(map, i)) {
|
|
*ret = i;
|
|
return 0;
|
|
}
|
|
i++;
|
|
if (i >= fs->super->s_blocks_count)
|
|
i = fs->super->s_first_data_block;
|
|
} while (i != goal);
|
|
return EXT2_ET_BLOCK_ALLOC_FAIL;
|
|
}
|
|
|
|
/*
|
|
* This function zeros out the allocated block, and updates all of the
|
|
* appropriate filesystem records.
|
|
*/
|
|
errcode_t ext2fs_alloc_block(ext2_filsys fs, blk_t goal,
|
|
char *block_buf, blk_t *ret)
|
|
{
|
|
errcode_t retval;
|
|
blk_t block;
|
|
char *buf = 0;
|
|
|
|
if (!block_buf) {
|
|
retval = ext2fs_get_mem(fs->blocksize, &buf);
|
|
if (retval)
|
|
return retval;
|
|
block_buf = buf;
|
|
}
|
|
memset(block_buf, 0, fs->blocksize);
|
|
|
|
if (!fs->block_map) {
|
|
retval = ext2fs_read_block_bitmap(fs);
|
|
if (retval)
|
|
goto fail;
|
|
}
|
|
|
|
retval = ext2fs_new_block(fs, goal, 0, &block);
|
|
if (retval)
|
|
goto fail;
|
|
|
|
retval = io_channel_write_blk(fs->io, block, 1, block_buf);
|
|
if (retval)
|
|
goto fail;
|
|
|
|
ext2fs_block_alloc_stats(fs, block, +1);
|
|
*ret = block;
|
|
return 0;
|
|
|
|
fail:
|
|
if (buf)
|
|
ext2fs_free_mem(&buf);
|
|
return retval;
|
|
}
|
|
|
|
errcode_t ext2fs_get_free_blocks(ext2_filsys fs, blk_t start, blk_t finish,
|
|
int num, ext2fs_block_bitmap map, blk_t *ret)
|
|
{
|
|
blk_t b = start;
|
|
|
|
EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
|
|
|
|
if (!map)
|
|
map = fs->block_map;
|
|
if (!map)
|
|
return EXT2_ET_NO_BLOCK_BITMAP;
|
|
if (!b)
|
|
b = fs->super->s_first_data_block;
|
|
if (!finish)
|
|
finish = start;
|
|
if (!num)
|
|
num = 1;
|
|
do {
|
|
if (b+num-1 > fs->super->s_blocks_count)
|
|
b = fs->super->s_first_data_block;
|
|
if (ext2fs_fast_test_block_bitmap_range(map, b, num)) {
|
|
*ret = b;
|
|
return 0;
|
|
}
|
|
b++;
|
|
} while (b != finish);
|
|
return EXT2_ET_BLOCK_ALLOC_FAIL;
|
|
}
|
|
|