mdoc(7) police: Scheduled sweep.
Killed one more instance of pseudo-devices.
Fixed copyright.
Tidy up the markup.
Only describe the new, post-2.0 behavior.
Added the RETURN VALUES and ERRORS sections.
So we don't use this header anymore.
Install the gcov(1) manpage; kernbb(8) references it.
Fixed a typo in MLINKS.
mdoc(7) police: Tidy up.
Only apply rev 1.10 (which hacks around the i386 boot2 being too big for
both ufs1 and ufs2 support) on i386.
Remove support for running in SimOS. The support has rotted over
time and there's no indication that it will improve anytime soon.
By removing support for SimOS it is possible to build LINT on
Alpha, which is considered more important at the moment.

Not objected to on: alpha@
Hold the TCP protocol lock while modifying the connection hash table.
Cleanup of the d_mmap_t interface.

- Get rid of the useless atop() / pmap_phys_address() detour.  The
  device mmap handlers must now give back the physical address
  without atop()'ing it.
- Don't borrow the physical address of the mapping in the returned
  int.  Now we properly pass a vm_offset_t * and expect it to be
  filled by the mmap handler when the mapping was successful.  The
  mmap handler must now return 0 when successful, any other value
  is considered as an error.  Previously, returning -1 was the only
  way to fail.  This change thus accidentally fixes some devices
  which were bogusly returning errno constants which would have been
  considered as addresses by the device pager.
- Garbage collect the poorly named pmap_phys_address() now that it's
  no longer used.
- Convert all the d_mmap_t consumers to the new API.

I'm still not sure wheter we need a __FreeBSD_version bump for this,
since and we didn't guarantee API/ABI stability until 5.1-RELEASE.

Discussed with:		alc, phk, jake
Reviewed by:		peter
Compile-tested on:	LINT (i386), GENERIC (alpha and sparc64)
Runtime-tested on:	i386
 - Add an interlock argument to BUF_LOCK and BUF_TIMELOCK.
 - Remove the buftimelock mutex and acquire the buf's interlock to protect
   these fields instead.
 - Hold the vnode interlock while locking bufs on the clean/dirty queues.
   This reduces some cases from one BUF_LOCK with a LK_NOWAIT and another
   BUF_LOCK with a LK_TIMEFAIL to a single lock.

Reviewed by:	arch, mckusick
Remove a never true condition.
Remove a bogus comment.
Prevent large files from monopolizing the system buffers. Keep
track of the number of dirty buffers held by a vnode. When a
bdwrite is done on a buffer, check the existing number of dirty
buffers associated with its vnode. If the number rises above
vfs.dirtybufthresh (currently 90% of vfs.hidirtybuffers), one
of the other (hopefully older) dirty buffers associated with
the vnode is written (using bawrite). In the event that this
approach fails to curb the growth in it the vnode's number of
dirty buffers (due to soft updates rollback dependencies),
the more drastic approach of doing a VOP_FSYNC on the vnode
is used. This code primarily affects very large and actively
written files such as snapshots. This change should eliminate
hanging when taking snapshots or doing background fsck on
very large filesystems.

Hopefully, one day it will be possible to cache filesystem
metadata in the VM cache as is done with file data. As it
stands, only the buffer cache can be used which limits total
metadata storage to about 20Mb no matter how much memory is
available on the system. This rather small memory gets badly
thrashed causing a lot of extra I/O. For example, taking a
snapshot of a 1Tb filesystem minimally requires about 35,000
write operations, but because of the cache thrashing (we only
have about 350 buffers at our disposal) ends up doing about
237,540 I/O's thus taking twenty-five minutes instead of four
if it could run entirely in the cache.

Reported by:	Attila Nagy <bra@fsn.hu>
Sponsored by:   DARPA & NAI Labs.
Fuse two #ifdefs with identical conditions.
Retire major #133 (amrd).
NO_GEOM cleanup:

Move to "struct disk*" centric API.
Retire major #131 (mlxd)
More fixes.

Submitted by:	Andy Farkas <andyf@speednet.com.au>
Reviewed by:	das
NO_GEOM cleanup:

Move to new "struct disk *" centric API.
Retire major #147 (twed)