superblock. Avoids false positives should fsck_ffs be run on a filesystem
that was created after the UFS2 code has been merged.
This commit is mostly a forward compatibility patch that can be pulled
up in to the 1.6 branch.
From Kirk Mckusick in FreeBSD (setup.c rev. 1.30). Original commit message:
========
When checking the alternate superblock, we used to copy any fields
that might have changed, then did a byte-by-byte comparison with
the alternate. If any unused fields got used, they had to be added
to the exception list. Such changes caused too many false alarms.
So, I have changed the comparison algorithm to compare a selected
set of fields that are not expected to change. This new algorithm
causes far fewer false hits and still does a good job of detecting
problems when they have really occurred. In particular, this change
should ease the transition to kernels supporting UFS2 which make
some significant changes to the superblock.
Sponsored by: DARPA, NAI Labs
========
I didn't have time to clean it up completely before my legal status
w.r.t. open source projects goes into limbo for a while. Other
developers are encouraged to play with the tool and get it into
release-worthy shape.
TODO list (see TODO file)
* verify it builds on -current, put it into release lists/etc. and src/sbin/Makefile
(built & tested on 1.6.1)
* make it ask questions before doing any work (confirm)
* create regression test suite (see discussions on tech-kern and
developers) and fix any bugs
* verify conversion to ANSI C didn't break anything
* port to UFS2
(there are still some details to work out) but expect that to go
away soon. To support these basic changes (creation of lfs_putpages,
lfs_gop_write, mods to lfs_balloc) several other changes were made, to
wit:
* Create a writer daemon kernel thread whose purpose is to handle page
writes for the pagedaemon, but which also takes over some of the
functions of lfs_check(). This thread is started the first time an
LFS is mounted.
* Add a "flags" parameter to GOP_SIZE. Current values are
GOP_SIZE_READ, meaning that the call should return the size of the
in-core version of the file, and GOP_SIZE_WRITE, meaning that it
should return the on-disk size. One of GOP_SIZE_READ or
GOP_SIZE_WRITE must be specified.
* Instead of using malloc(...M_WAITOK) for everything, reserve enough
resources to get by and use malloc(...M_NOWAIT), using the reserves if
necessary. Use the pool subsystem for structures small enough that
this is feasible. This also obsoletes LFS_THROTTLE.
And a few that are not strictly necessary:
* Moves the LFS inode extensions off onto a separately allocated
structure; getting closer to LFS as an LKM. "Welcome to 1.6O."
* Unified GOP_ALLOC between FFS and LFS.
* Update LFS copyright headers to correct values.
* Actually cast to unsigned in lfs_shellsort, like the comment says.
* Keep track of which segments were empty before the previous
checkpoint; any segments that pass two checkpoints both dirty and
empty can be summarily cleaned. Do this. Right now lfs_segclean
still works, but this should be turned into an effectless
compatibility syscall.
compile-time by BRIDGE_IPF, and at runtime by brconfig with the {ipf,-ipf}
option on a per-bridge basis.
As a side-effect, add PFIL_HOOKS processing to if_bridge.
and names a file, use that as a the default kernel, otherwise fall
back to /netbsd.
Makes lkms work *much* better when you're testing kernels that are not
named /netbsd.
effectively making the currently selected configuration the only one
active and removing boot configuration selection menu.
This is accomplished by running 'newbtconf revert'.
From PR bin/17808 by myself. Thanks to gendalia and lukem for the help finding
the right keyword.
Approved by lukem.
for forking the traditional UNIX init(8) and it does the Mach port naming
service. We need mach_init for the naming service, but unfortunately, it
will only act as such if its PID is 1. We introduce a sysctl
(emul.darwin.init_pid) to fool a given process into thinking its PID is 1.
That way we can get mach_init into behaving as the name server.
Typical use:
/sbin/sysctl -w emul.darwin.init_pid=$$ ; exec /emul/darwin/sbin/mach_init
martin