Implemented by changing write_map to accept a WMAP_FREE flag. In that
case, it doesn't update the datablock (creating indirect zones as
necessary) pointer, but it frees the datablock if present. Also it
frees the single and double indirect blocks if unused.
This makes the implementation of truncate_inode() simpler.
truncate_inode() now accepts a truncation length which makes
implementing truncate() and ftruncate() simple.
This also allowed implementing the F_FREESP fcntl().
. new_node() now returns inode of parent dir as argument that
has to be put_node()d again by the caller of new_node().
it can also return the name of the last component as last_dir()
did.
. advance() takes a pointer to a pointer of an inode as the
parent now. This parent can change, in which case the old
one is put_node()d and a new one is put there.
. eat_path() replaced by more flexible parse_path()
. last_dir() replaced by call to parse_path().
. do_slink(), do_readlink(), do_lstat() and slink_traverse() added.
Also added some truncate()/ftruncate()-introduction related changes.
(e.g. renamed truncate() to truncate_inode().)
. When drivers disappear that have pending select()s, wake up
those user processes with EAGAIN so that they can retry their
select() and won't hang forever on it.
. When drivers re-appear and are mapped into the dmap, run through
the list of mounted filesystems and re-dev_open() every one (for
partition tables and such). This can't happen before the driver
has exec()ced itself, so processes that have fork()ed but not
exec()ced yet are marked as DMAP_BABY in the dmap table if they
are dmapped before they are execced. If that happens, the above
procedure happens after the exec(). If the exec() happens before
the dmapping, it (the dev_open()ing) happens right away.
New Shift-F6 dump for RS server at IS.
New getnpid, getnproc, getpproc library calls at PM.
New reincarnation server (basic functionality is there now).
. unmap device drivers from dmap when PM signals they are dead
. new null-io function (no_dev_io) to fill in for io functions
of unmapped drivers
. driver (process number) of unmapped drivers is NONE instead of
0 (a valid process number)
IS:
. print mutable flag of dmap table too
FS changes require sync() to be done 'manually' (currently by
reboot/shutdown) at shutdown time; could be caught by SIGTERM in
the future.
enforced. If a call is denied, this will be kprinted. Please report any such
errors, so that I can adjust the mask before returning errors instead of
warnings.
Wrote CMOS driver. All CMOS code from FS has been removed. Currently the
driver only supports get time calls. Set time is left out as an exercise
for the book readers ... startup scripts were updated because the CMOS driver
is needed early on. (IS got same treatment.) Don't forget to run MAKEDEV cmos
in /dev/, otherwise the driver cannot be loaded.
The user needs to set label=... to choose the driver of his or her choice.
This driver will be mapped onto the controller that is set in controller=...
Minor cleanup of kernel source code (boot image table now is static).
