busybox/e2fsprogs/ext2fs/bmove.c
2005-09-24 07:10:37 +00:00

161 lines
3.5 KiB
C

/*
* bmove.c --- Move blocks around to make way for a particular
* filesystem structure.
*
* Copyright (C) 1997 Theodore Ts'o. This file may be redistributed
* under the terms of the GNU Public License.
*/
#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#if HAVE_SYS_TIME_H
#include <sys/time.h>
#endif
#include "ext2fs/ext2_fs.h"
#include "ext2fs/ext2fsP.h"
struct process_block_struct {
ext2_ino_t ino;
struct ext2_inode * inode;
ext2fs_block_bitmap reserve;
ext2fs_block_bitmap alloc_map;
errcode_t error;
char *buf;
int add_dir;
int flags;
};
static int process_block(ext2_filsys fs, blk_t *block_nr,
e2_blkcnt_t blockcnt, blk_t ref_block,
int ref_offset, void *priv_data)
{
struct process_block_struct *pb;
errcode_t retval;
int ret;
blk_t block, orig;
pb = (struct process_block_struct *) priv_data;
block = orig = *block_nr;
ret = 0;
/*
* Let's see if this is one which we need to relocate
*/
if (ext2fs_test_block_bitmap(pb->reserve, block)) {
do {
if (++block >= fs->super->s_blocks_count)
block = fs->super->s_first_data_block;
if (block == orig) {
pb->error = EXT2_ET_BLOCK_ALLOC_FAIL;
return BLOCK_ABORT;
}
} while (ext2fs_test_block_bitmap(pb->reserve, block) ||
ext2fs_test_block_bitmap(pb->alloc_map, block));
retval = io_channel_read_blk(fs->io, orig, 1, pb->buf);
if (retval) {
pb->error = retval;
return BLOCK_ABORT;
}
retval = io_channel_write_blk(fs->io, block, 1, pb->buf);
if (retval) {
pb->error = retval;
return BLOCK_ABORT;
}
*block_nr = block;
ext2fs_mark_block_bitmap(pb->alloc_map, block);
ret = BLOCK_CHANGED;
if (pb->flags & EXT2_BMOVE_DEBUG)
printf("ino=%ld, blockcnt=%lld, %d->%d\n", pb->ino,
blockcnt, orig, block);
}
if (pb->add_dir) {
retval = ext2fs_add_dir_block(fs->dblist, pb->ino,
block, (int) blockcnt);
if (retval) {
pb->error = retval;
ret |= BLOCK_ABORT;
}
}
return ret;
}
errcode_t ext2fs_move_blocks(ext2_filsys fs,
ext2fs_block_bitmap reserve,
ext2fs_block_bitmap alloc_map,
int flags)
{
ext2_ino_t ino;
struct ext2_inode inode;
errcode_t retval;
struct process_block_struct pb;
ext2_inode_scan scan;
char *block_buf;
retval = ext2fs_open_inode_scan(fs, 0, &scan);
if (retval)
return retval;
pb.reserve = reserve;
pb.error = 0;
pb.alloc_map = alloc_map ? alloc_map : fs->block_map;
pb.flags = flags;
retval = ext2fs_get_mem(fs->blocksize * 4, &block_buf);
if (retval)
return retval;
pb.buf = block_buf + fs->blocksize * 3;
/*
* If GET_DBLIST is set in the flags field, then we should
* gather directory block information while we're doing the
* block move.
*/
if (flags & EXT2_BMOVE_GET_DBLIST) {
if (fs->dblist) {
ext2fs_free_dblist(fs->dblist);
fs->dblist = NULL;
}
retval = ext2fs_init_dblist(fs, 0);
if (retval)
return retval;
}
retval = ext2fs_get_next_inode(scan, &ino, &inode);
if (retval)
return retval;
while (ino) {
if ((inode.i_links_count == 0) ||
!ext2fs_inode_has_valid_blocks(&inode))
goto next;
pb.ino = ino;
pb.inode = &inode;
pb.add_dir = (LINUX_S_ISDIR(inode.i_mode) &&
flags & EXT2_BMOVE_GET_DBLIST);
retval = ext2fs_block_iterate2(fs, ino, 0, block_buf,
process_block, &pb);
if (retval)
return retval;
if (pb.error)
return pb.error;
next:
retval = ext2fs_get_next_inode(scan, &ino, &inode);
if (retval == EXT2_ET_BAD_BLOCK_IN_INODE_TABLE)
goto next;
}
return 0;
}