Change the interfaces of these functions to save space. The code
that takes the least amount of space is often the opposite to what
you might expect. E.g., it helps to waste a few bytes passing
pointers so that the compiler can't see that certain addresses
are identical (gcc likes to waste space by reloading fat constants
even when the constant is already in a register).
Rewrite getbootdev() to save 80 bytes of space and to make it less
ugly. 32 bytes were saved simply by omitting the continue statements
in the pseudo-switch.
recently introduced bloat in just 2 calls to biosread(), although
very little in calls to putc() and serial_putc(). Gcc produces
amazingly bad code for unnecessary conversions. E.g., if it has
`int x' in register %edx and wants to pass a char, then it could
simply push %edx and access only one byte in the callee. Instead,
it sometimes unnecessarily spills %edx; it always sign extends
%edx and pushes the result.
Remove useless `extern' in function prototypes.
Remove unused declaration of `end'.
Declare pbzero() and pcpy() like the library bzero and bcopy().
Declare printf() properly.
do fit, and beeping in case of an overflow.
. Drop a comment about the ``FORCE_COMCONSOLE'' option into
README.serial.
. Increase the name buffer for the root directory from 100 bytes
to 8 KB; this is in no way ideal, but (IMHO) the best that can
be done by now. People did encounter problems with their root
dir name listing overflowing the allocated buffer space. Once
we've got the three-stage boot, we should implement some basic
malloc(). Swap space is already getting tight now, perhaps the
swap should go into another 64 KB segment instead.
. Make the keyboard probe less paranoid. It should not give up in
case of a keyboard that's continuously demanding RESEND's. Even
though the keyboard reset apparently has not been reported to be
complete, it's at the very least proven that there IS something
like a keyboard available.
This solves problems with the ``Gateway-2000 AllKey programmable''
(sp?) keyboard, that experienced a total hang with the previous
probe.
Thanks goes to Scott Blachowicz <scott@statsci.com> for his
extensive testing of my various interim (debugging) bootblocks
to get this working.
some (hopefully) less offensive stupidity:
If we detect that a user has loaded a module that fails to initialize
itself correctly, panic. There really isn't a safe way to recover from
something like this; we can't know that the module is bad until after
the entry point is called, by which time it's too late to do anything
about it.
- Add $Id$ string.
- Fix comment ("we might *not* be able to unload the
module afterwards without panicking...")
- Get rid of variable 'j' that I used in name checking
for(;;) loop and use 'i' instead (I thought there'd be
a problem with this, but there isn't).
got a 2.2 version DC21040 chip in my SMC ethernet card! He suggests bumping
the check all the way down to 2.0 since it's pre-2.0 we're actually guarding
against.
Submitted by: Matt Thomas <matt@lkg.dec.com>
if_tun_mod, etc...) from crashing the system. These modules are useful,
but because they don't yet have proper load()/unload() functions,
they can lead to panics: if, for example, you load the if_ppp module,
any user can panic the system by running modstat.
You can also hang the system outright if you try to unload the PPP
module too.
Changes are as follows:
- Save the name passed to us during the RESERVE stage for name matching
(we can't load if_ppp_mod twice: we've have two ppp0's and two ppp1's,
which is beyond strange). This makes the lkmexists() cheks somewhat
redundant, but there's no way around it that I can see.
- If we call the module entry point and find that we have no lkm_any
structure in our 'private' section, create a fake one. This keeps
modstat happy. We mark such modules as LM_UNKNOWN.
- Don't allow LM_UNLOAD modules to be unloaded: it just ain't
possible. (Unless someone wants to write a pppunattach() function. :( )
- In lkmunreserve(), mark private.lkm_any as NULL so we don't get
confused later. I think this is bogus, but I can't prove it.
XXX: the name matching used to keep the user from loading two
instances of the same module can easily be defeated simply by
changing the module name or, in the case of the oddball modules,
simply by renaming the module files. I haven't found a nice simple
way to tell one module from another.
interested parties.
Make the loader refuse to load anything below 1 MB -- we didn't
support it since FreeBSD 2.0R. Avoid gratuitously wiping out the BIOS
variables or the loader.
