avoid having to allocate space in the 'stackgap'
- which is very LWP unfriendly.
The additional code for non-emulation namei() is trivial, the reduction for
the emulations is massive.
The vnode for a processes emulation root is saved in the cwdi structure
during process exec.
If the emulation root the TRYEMULROOT flag are set, namei() will do an initial
search for absolute pathnames in the emulation root, if that fails it will
retry from the normal root.
".." at the emulation root will always go to the real root, even in the middle
of paths and when expanding symlinks.
Absolute symlinks found using absolute paths in the emulation root will be
relative to the emulation root (so /usr/lib/xxx.so -> /lib/xxx.so links
inside the emulation root don't need changing).
If the root of the emulation would be returned (for an emulation lookup), then
the real root is returned instead (matching the behaviour of emul_lookup,
but being a cheap comparison here) so that programs that scan "../.."
looking for the root dircetory don't loop forever.
The target for symbolic links is no longer mangled (it used to get the
CHECK_ALT_xxx() treatment, so could get /emul/xxx prepended).
CHECK_ALT_xxx() are no more. Most of the change is deleting them, and adding
TRYEMULROOT to the flags to NDINIT().
A lot of the emulation system call stubs could now be deleted.
the LKM.
While there, rename 'rval' as 'pn_family', and make it a global variable.
The k[78]_powernow_destroy() functions have never been called because of
that...
The problem was that pnowk7_init() was called too early in the boot
process, at this point the required calls were not available.
Thanks to Rhialto for testing and cube/christos for comments.
The code supports read access to all media types that CD/DVD type drives
can recognize including DVD-RAM and BD- drives as well as harddisc partions
and vnd devices. UDF versions upto the latest 2.60 are to be supported
though due to lack of test media version 2.50 and 2.60 are not implemented
yet though easy to add. Both open and closed media are supported.
Write access is planned and in preparation. To facilitate this some hooks
are present in the code that are not strictly needed in a read-only
implementation but which allow writing to be added more easily.
Implemented and tested media types are CD-ROM, CD-R, CD-RW, CD-MRW,
DVD-ROM, DVD*R, DVD*RW, DVD+MRW but the same code can also read DVD-RAM,
HD-DVD and BluRay discs. Also vnd devices have been tested with several
sector sizes.
Discs created and written by UDFclient, Nero's InCD and Roxio's
DirectCD/Drag2Disc read fine.
