void do_zeroi(int argc, char *argv[])
{
if (check_fs_open(argv[0]))
return;
printf("Clearing inode bitmap.\n");
ext2fs_clear_inode_bitmap(test_fs->inode_map);
}
/*
* This subroutine is responsible for making sure that a particular
* directory is connected to the root; if it isn't we trace it up as
* far as we can go, and then offer to connect the resulting parent to
* the lost+found. We have to do loop detection; if we ever discover
* a loop, we treat that as a disconnected directory and offer to
* reparent it to lost+found.
*
* However, loop detection is expensive, because for very large
* filesystems, the inode_loop_detect bitmap is huge, and clearing it
* is non-trivial. Loops in filesystems are also a rare error case,
* and we shouldn't optimize for error cases. So we try two passes of
* the algorithm. The first time, we ignore loop detection and merely
* increment a counter; if the counter exceeds some extreme threshold,
* then we try again with the loop detection bitmap enabled.
*/
static int check_directory(e2fsck_t ctx, ext2_ino_t dir,
struct problem_context *pctx)
{
ext2_filsys fs = ctx->fs;
ext2_ino_t ino = dir, parent;
int loop_pass = 0, parent_count = 0;
while (1) {
/*
* Mark this inode as being "done"; by the time we
* return from this function, the inode we either be
* verified as being connected to the directory tree,
* or we will have offered to reconnect this to
* lost+found.
*
* If it was marked done already, then we've reached a
* parent we've already checked.
*/
if (ext2fs_mark_inode_bitmap2(inode_done_map, ino))
break;
if (e2fsck_dir_info_get_parent(ctx, ino, &parent)) {
fix_problem(ctx, PR_3_NO_DIRINFO, pctx);
return 0;
}
/*
* If this directory doesn't have a parent, or we've
* seen the parent once already, then offer to
* reparent it to lost+found
*/
if (!parent ||
(loop_pass &&
(ext2fs_test_inode_bitmap2(inode_loop_detect,
parent)))) {
pctx->ino = ino;
if (fix_problem(ctx, PR_3_UNCONNECTED_DIR, pctx)) {
if (e2fsck_reconnect_file(ctx, pctx->ino))
ext2fs_unmark_valid(fs);
else {
fix_dotdot(ctx, pctx->ino,
ctx->lost_and_found);
parent = ctx->lost_and_found;
}
}
break;
}
ino = parent;
if (loop_pass) {
ext2fs_mark_inode_bitmap2(inode_loop_detect, ino);
} else if (parent_count++ > 2048) {
/*
* If we've run into a path depth that's
* greater than 2048, try again with the inode
* loop bitmap turned on and start from the
* top.
*/
loop_pass = 1;
if (inode_loop_detect)
ext2fs_clear_inode_bitmap(inode_loop_detect);
else {
pctx->errcode = e2fsck_allocate_inode_bitmap(fs, _("inode loop detection bitmap"), EXT2FS_BMAP64_AUTODIR, "inode_loop_detect", &inode_loop_detect);
if (pctx->errcode) {
pctx->num = 1;
fix_problem(ctx,
PR_3_ALLOCATE_IBITMAP_ERROR, pctx);
ctx->flags |= E2F_FLAG_ABORT;
return -1;
}
}
ino = dir;
}
}
/*
* Make sure that .. and the parent directory are the same;
* offer to fix it if not.
*/
pctx->ino = dir;
if (e2fsck_dir_info_get_dotdot(ctx, dir, &pctx->ino2) ||
e2fsck_dir_info_get_parent(ctx, dir, &pctx->dir)) {
fix_problem(ctx, PR_3_NO_DIRINFO, pctx);
return 0;
}
if (pctx->ino2 != pctx->dir) {
if (fix_problem(ctx, PR_3_BAD_DOT_DOT, pctx))
fix_dotdot(ctx, dir, pctx->dir);
}
return 0;
}