[LTP] [PATCH v3 2/2] lib/tst_test.c: Add .needs_devfs flag

[Cyril Hrubis <chrubis@suse.cz>]

Hi!
> +static void prepare_and_mount_dev_fs(const char *mntpoint)
> +{
> +	const char *flags[] = {"nodev", NULL};
> +	char abs_path[PATH_MAX];
> +
> +	sprintf(abs_path, "%s/%s", tst_get_tmpdir(), mntpoint);

The tst_get_tmpdir() allocates memory and also we are sure that mntpoint
is on the same filesystem as the path returned by tst_get_tmpdir().

So I would suggest something like this:

	char *tmpdir;
	int mounted_nodev;

	tmpdir = tst_get_tmpdir();
	mounted_nodev = tst_path_has_mnt_flags(NULL, tmpdir, flags);
	free(tmpdir);

	if (mounted_nodev) {
		...
	}

> +	if (tst_path_has_mnt_flags(NULL, abs_path, flags)) {
> +		tst_res(TINFO, "%s isn't suitable for creating devices, "
> +			"so mount tmpfs without nodev over it", abs_path);
> +		SAFE_MOUNT(NULL, mntpoint, "tmpfs", 0, NULL);
> +		mntpoint_mounted = 1;
> +	}
> +}
> +
>  static void prepare_device(void)
>  {
>  	if (tst_test->format_device) {
> @@ -786,11 +801,15 @@ static void do_setup(int argc, char *argv[])
>  	if (tst_test->mntpoint)
>  		SAFE_MKDIR(tst_test->mntpoint, 0777);
>  
> -	if ((tst_test->needs_rofs || tst_test->mount_device ||
> -	     tst_test->all_filesystems) && !tst_test->mntpoint) {
> +	if ((tst_test->needs_devfs || tst_test->needs_rofs ||
> +	     tst_test->mount_device || tst_test->all_filesystems) &&
> +	     !tst_test->mntpoint) {
>  		tst_brk(TBROK, "tst_test->mntpoint must be set!");
>  	}

I guess that we should also make sure only one of needs_rofs,
needs_devfs or needs_device is set, because otherwise we would attempt
to mount multiple filesystems over the mntpoint.

something as:

	if (!!tst_test->needs_rofs +
	    !!tst_test->needs_devfs +
	    !!tst_test->needs_device > 1) {
		tst_brk(TBROK, "Two or more of needs_{rofs, devfs, device} are set");
	}

> +	if (tst_test->needs_devfs)
> +		prepare_and_mount_dev_fs(tst_test->mntpoint);
> +
>  	if (tst_test->needs_rofs) {
>  		/* If we failed to mount read-only tmpfs. Fallback to
>  		 * using a device with read-only filesystem.

Other than the minor nits this version looks fine.

-- 
Cyril Hrubis
chrubis@suse.cz