[LTP] [PATCH v5] listmount04.c: Update case support mnt_id_req.mnt_ns_fd

[Cyril Hrubis]

Hi!
> > -#ifndef HAVE_STRUCT_MNT_ID_REQ
> > -struct mnt_id_req {
> > +struct mnt_id_req_fallback {
> >  	uint32_t size;
> > -	uint32_t spare;
> > +	uint32_t mnt_ns_fd;
> >  	uint64_t mnt_id;
> >  	uint64_t param;
> >  	uint64_t mnt_ns_id;
> >  };
> > +
> > +#if !defined(HAVE_STRUCT_MNT_ID_REQ) || !HAVE_STRUCT_MNT_ID_REQ_MNT_NS_FD
> Shouldn't be !HAVE_STRUCT_MNT_ID_REQ_MNT_NS_FD
> !defined(HAVE_STRUCT_MNT_ID_REQ_MNT_NS_FD) ?
> 
> Also, this patchset introduces compilation error on old systems:
> 
> In file included from listmount03.c:13:0:
> listmount.h:20:4: error: 'struct mnt_id_req' has no member named 'mnt_id'
>    .mnt_id = mnt_id,
> 
> Obviously some definition is wrong.

That looks like we need configure check for mnt_id too however that
happens in a different test.

> https://github.com/pevik/ltp/actions/runs/20166087670/job/57889711762
> 
> (CI does not work, therefore I pushed you patchset.)
> 
> > +typedef struct mnt_id_req_fallback mnt_id_req;
> > +#else
> > +typedef struct mnt_id_req mnt_id_req;
> >  #endif
> 
> ...
> > +static void setup(void)
> > +{
> > +	if (tst_kvercmp(6, 18, 0) >= 0) {
> > +		tcases[4].exp_errno = EBADF;
> > +		tcases[4].msg = "invalid mnt_id_req.mnt_ns_fd (EBADF)";
> 
> Hardcoding array index is asking for problems in the future.
> 
> That's why I suggested more complicated code in previous version.
> https://lore.kernel.org/ltp/20251211115111.GA63924@pevik/

Another solution would be to define testcases for both for EINVAL and
EBADF and add a flag which should be enabled on newer kernel:

#define BEFORE_6_18 1
#define AFTER_6_18 2

...
	{
                .req_usage = 1,
                .size = MNT_ID_REQ_SIZE_VER0,
                .spare = -1,
                .mnt_id = LSMT_ROOT,
                .mnt_ids = mnt_ids,
                .nr_mnt_ids = MNT_SIZE,
                .exp_errno = EINVAL,
                .msg = "invalid mnt_id_req.spare",
		.kver = BEFORE_6_18,
        },
	{
                .req_usage = 1,
                .size = MNT_ID_REQ_SIZE_VER0,
                .spare = -1,
                .mnt_id = LSMT_ROOT,
                .mnt_ids = mnt_ids,
                .nr_mnt_ids = MNT_SIZE,
                .exp_errno = EBADF,
                .msg = "invalid mnt_id_req.mnt_nf_fd",
		.kver = AFTER_6_18,
        },
...

static void run(...)
{
	...

	if (tc->kver && tc->kver != kver)
		return;

	...
}

static void setup(void)
{
	if (tst_kvercmp(6, 18, 0) >= 0)
		kver = AFTER_6_18;
	else
		kver = BEFORE_6_18;
}


-- 
Cyril Hrubis
chrubis@suse.cz