[LTP] isofs.sh rewrite [was Re: [PATCH 2/6] tst_env.sh: Backport common functions from tst_test.sh]

[Petr Vorel]

Hi Cyril,

...
Let's change the mail subject for this.

> > But OTOH maybe route-change-*.sh tests even don't need to quit.
> > And it's a question if isofs.sh does (and whether we should even keep isofs.sh).

> For the isofs I would probably generate the iso filesystems in advance
> and store them in git so that we don't have to re-generate them during
> the test run. Other than that mounting an iso filesystem over loopback
> and checking that the files are there (which the test does not do) is
> valid kernel test. But that is a different problem.

Ah, right. It's both mkisofs/genisoimage/xorrisofs test + testing isofs as the
kernel part :). And sure, isofs itself will kept used for very long time (USB
install media).

I'll create a ticket once we agree what should be done. "Rewrite test to
mounting an iso filesystem over loopback and checking that the files are there."
is clear. Creating filesystem would be gen_fs_tree() calls (these subdirs) +
call one of mkisofs/genisoimage/xorrisofs. I guess TODO is to find out which
options are worth to test. Because test runs various options, testing ISO-9660
(various ISO levels)/JOLIET/UDF. Kernel's fs/isofs/Kconfig mentions
CONFIG_ISO9660_FS and two other depending on it: CONFIG_JOLIET and CONFIG_ZISOFS
(uses an old tool mkzftree).

Resulted ISO file has 9 MB, which is OK for git (given we are ok only with a
single variant). Obviously we are not going to test max files limits (e.g. files
over 2 GB for DVD require iso level 3), but hopefully size does not matter much.

I'm not sure if it's worth to test some invalid ISOs. But it'd be worth to add
max at least test for max file size, i.e recent fix from v7.0-rc1:
18a777eee289 ("isofs: support full length file names (255 instead of 253)")

Kind regards,
Petr