- the major number wasn't checked, so accesses beyond the end of bdevsw[]
were possible. Bogus major numbers are easy to get because `sysctl -w'
doesn't handle dev_t's reasonably - it doesn't convert names to dev_t's
and it converts the number 1025 to the dev_t 0x35323031.
- Driver d_psize() functions return -1 to indicate error ENXIO or ENODEV
(the interface is too braindamaged to say which). -1 was interpreted
as a size and resulted in the bogus error ENOSPC.
- it was possible to set the dumpdev for devices without a d_psize()
function. This is equivalent to setting the dumpdev to NODEV except
it confuses sysctl.
- change a 512 to DEV_BSIZE. There is an official macro dtoc() for
converting "pages" to disk blocks but it is never used in /usr/src/sys.
There is much confusion between PAGE_SIZE sized pages and NBPG sized
pages. Maxmem consists of both.
Not fixed:
- there is nothing to invalidate the dumpdev if the media goes away.
This reduces the benefits of the early calculation of dumplo. Bounds
checking in the dump routines is relied on to reduce the risk of
damage and little would be lost by relying on the dump routines to
calculate dumplo.
- no attempt is made to stay away from the start of the device to
avoid clobbering labels.
Fix wrong && anachronistic comment about the type of bootdev.
Reviewed by: davidg
Submitted by: Bruce Evans
require specific partitions be mentioned in the kernel config
file ("swap on foo" is now obsolete).
From Poul-Henning:
The visible effect is this:
As default, unless
options "NSWAPDEV=23"
is in your config, you will have four swap-devices.
You can swapon(2) any block device you feel like, it doesn't have
to be in the kernel config.
There is a performance/resource win available by getting the NSWAPDEV right
(but only if you have just one swap-device ??), but using that as default
would be too restrictive.
The invisible effect is that:
Swap-handling disappears from the $arch part of the kernel.
It gets a lot simpler (-145 lines) and cleaner.
Reviewed by: John Dyson, David Greenman
Submitted by: Poul-Henning Kamp, with minor changes by me.
boot diskless with it, you get a panic because setconf() is only
called for mountroot == ffs_mountroot. It really needs to be called
no matter what manner of rootfs we have. I can't really say if
swapgeneric will work with a CD-ROM though. (I get the feeling I'm
the only one who uses swapgeneric these days anyway.)
just thinking about it.
Two changes need to be made to allow 'config kernel swap generic' to
work properly without requiring any compile-time flags:
/usr/src/usr.sbin/config/mkswapconf.c: we need to define a dummy stub
for the setconf() function to replace the one in swapgeneric.c that
isn't available in non-generic configurations.
/usr/src/sys/i386/i386/autoconf.c: the -a boot flag causes setroot()
to be skipped and lets setconf() prompt the user for a root device.
If you skip setroot() in a non-generic kernel, you could get severely
hosed. To avoid this, we silently ignore the -a flag if rootdev != NODEV.
(rootdev is always initialized to NODEV in swapgeneric.c, so if
we find that rootdev is something other than NODEV, we know we're
not using a generic configuration.)
- /sys/i386/i386/swapgeneric.c is just plain broke. But fear not, for I
have unbroken it. One thing that swapgeneric.c does is walk through the
list of configured devices searching for a boot device. The only easy
way to accomplish this in 2.0 is to use Garret Wollman's kern_devconf
stuff. *BUT*, the head of the kern_devconf linked list (dc_list) is declared
static in /sys/kern/kern_devconf.c. This means that swapgeneric.c can't
see it at link time. I had to remove the 'static' keyword to get around
this little problem. I hope this doesn't break anything anywhere.
*Furthermore,* there's a small matter of making the call to setconf()
in swapgeneric.c disappear when 'config kernel swap generic' isn't used.
You could change /sbin/config to create a dummy setconf() function in
swapkernel.c, but that seems messy somehow. (It's also someting of an
'it isn't broken, why are you fixing it' situation.) My solution was to
do what the NetBSD people did and put an #ifdef GENERIC around the call
to setconf(). If your kernel is called GENERIC or you define 'options
GENERIC,' then you can use 'config kernel swap generic' and it'll work.
That aside, the upshot is that: a) swapgeneric.c actually works, and
and b) the -a boot flag now works as well. If you boot with -a, as in
"Boot: wd(0,a)/kernel -a" you will be presented with a 'root device?'
prompt after the autoconfig phase, at which point you can specify what
device you want mounted as root. Regrettably, you can't specify an NFS
filesystem. Yet. Three files are affected: /sys/i386/i386/swapgeneric.c,
/sys/i386/i386/autoconf.c and /sys/kern/kern_devconf.c.
Submitted by: wpaul
``changes'' are actually not changes at all, but CVS sometimes has trouble
telling the difference.
This also includes support for second-directory compiles. This is not
quite complete yet, as `config' doesn't yet do the right thing. You can
still make it work trivially, however, by doing the following:
rm /sys/compile
mkdir /usr/obj/sys/compile
ln -s M-. /sys/compile
cd /sys/i386/conf
config MYKERNEL
cd ../../compile/MYKERNEL
ln -s /sys @
rm machine
ln -s @/i386/include machine
make depend
make
a binary link-kit. Make all non-optional options (pagers, procfs) standard,
and update LINT to reflect new symtab requirements.
NB: -Wtraditional will henceforth be forgotten. This editing pass was
primarily intended to detect any constructions where the old code might
have been relying on traditional C semantics or syntax. These were all
fixed, and the result of fixing some of them means that -Wall is now a
realistic possibility within a few weeks.
