numbers that we have been doing in the past, and read /etc/fstab off the
proposed root filesystem to determine the actual device name and vfs
type for the root filesystem. These are then exported to the kernel
via the environment variable vfs.root.mountfrom.
This should resolve the problem raised in PR 12315, and incidentally
makes it easier to determine what geometry the BIOS is actually using
(by way of boot -v and dmesg).
flag to the kernel to mount a CDROM as the root filesystem. Alternatively,
the boot_cdrom env var can be set.
As Mike Smith noted, "-C is the "wrong" way to do this", but this is
an acceptable stopgap in lieu of a better way.
PR: bin/11884
Reviewed by: msmith@freebsd.org
Implement a new variable 'root_disk_unit' which supersedes
'num_ide_disks' and makes it possible to explicitly set the
root device unit number regardless of type considerations.
bootinfo.c
If we can't calculate a dev_t for the root disk, complain and
don't proceed to boot with an invalid boot device.
should be MD code since one day we'll have to recover pages from deleted
preload data. MI code can't be expected to know how to deal with pmap
internals, assuming it gets done via pmap that is. :-)
Do a much better job of DWIM with partial device specifications.
Fix the module metadata build process, which was completely broken.
Use a larger read buffer when copying large objects in; this
improves performance marginally and will avoid flushning any small caches
we might choose to implement.
Strip any device name information from the kernel name
before passing it in.
biosdisk.c
Be more strict about matching device names to slice entries.
Only allow unsliced syntax on unsliced disks.
- Discard large amounts of BIOS-related code in favour of the more compact
BTX vm86 interface.
- Build the loader module as ELF, although the resulting object is a.out,
make gensetdefs 32/64-bit sensitive and use a single copy of it.
- Throw away installboot, as it's no longer required.
- Use direct bcopy operations in the i386_copy module, as BTX
maps the first 16M of memory. Check operations against the
detected size of actual memory.
- Use format-independant module allocator.
- Conditionalise ISA PnP support.
- Simplify PnP enumerator interface.
- Improve module/object searching.
- Add missing depend/install targets in BTX makefiles.
- Pass the kernel environment and module data in extended bootinfo fields.
- Add a pointer to the end of the kernel + modules in bootinfo.
- Fix parsing of old-style kernel arguments.
- Move some startup code from MD to MI sections
- Add a 'copyout' and some copyout-related functions. These will be
obsoleted when BTX is available for the 386 and the kernel load
area becomes directly addressable.
- Add the ability load an arbitrary file as a module, associating
and arbitrary type string with it. This can be used eg. for loading
splash-screen images etc.
- Add KLD module dependancy infrastructure. We know how to look for
dependancies inside KLD modules, how to resolve these dependancies
and what to do if things go wrong. Only works for a.out at the
moment, due to lack of an MI ELF loader. Attach KLD module information
to loaded modules as metadata, but don't pass it to the kernel (it
can find it itself).
- Load a.out KLD modules on a page boundary. Only pad the a.out BSS
for the kernel, as it may want to throw symbols away. (We might want
to do this for KLD modules too.)
- Allow commands to be hidden from the '?' display, to avoid cluttering
it with things like 'echo'. Add 'echo'.
- Bring the 'prompt' command into line with the parser syntax.
- Fix the verbose 'ls'; it was using an uninitialised stack variable.
- Add a '-v' flag to 'lsmod' to have it display module metadata as well
(not terribly useful for the average user)
- Support a 'module searchpath' for required modules.
- The bootstrap file on i386 is now called 'loader' to permit the
/boot directory to use that name.
- Discard the old i386 pread() function, as it's replaced by
arch_readin()
'three-stage' bootstrap.
There are a number of caveats with the code in its current state:
- The i386 bootstrap only supports booting from a floppy.
- The kernel and kld do not yet know how to deal with the extended
information and module summary passed in.
- PnP-based autodetection and demand loading of modules is not implemented.
- i386 ELF kernel loading is not ready yet.
- The i386 bootstrap is loaded via an ugly blockmap.
On the alpha, both net- and disk-booting (SRM console machines only) is
supported. No blockmaps are used by this code.
Obtained from: Parts from the NetBSD/i386 standalone bootstrap.
